Delphi

How protect Excel Sheet using Delphi?

2009-07-26T22:53:00.002-07:00

How protect Excel Sheet using Delphi?
Answer:

unit UTesteProtect;

interface

uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, StdCtrls, ComObj;

type
TForm1 = class(TForm)
Button1: TButton;
procedure Button1Click(Sender: TObject);
procedure FormDestroy(Sender: TObject);
private
{ Private declarations }
public
{ Public declarations }
end;

var
Form1: TForm1;
ExcelApp: OleVariant;

implementation

{$R *.dfm}

procedure TForm1.Button1Click(Sender: TObject);
const
// SheetType
xlChart = -4109;
xlWorksheet = -4167;
// WBATemplate
xlWBATWorksheet = -4167;
xlWBATChart = -4109;
// Page Setup
xlPortrait = 1;
xlLandscape = 2;
xlPaperA4 = 9;
// Format Cells
xlBottom = -4107;
xlLeft = -4131;
xlRight = -4152;
xlTop = -4160;
// Text Alignment
xlHAlignCenter = -4108;
xlVAlignCenter = -4108;
// Cell Borders
xlThick = 4;
xlThin = 2;
var
ColumnRange: OleVariant;

begin
{ Start Excel }

// By using GetActiveOleObject, you use an instance o
// f Word that's already running,
// if there is one.
try
// If no instance of Word is running, try to Create a new Excel Object
ExcelApp := CreateOleObject('Excel.Application');
except
ShowMessage('Cannot start Excel/Excel not installed ?');
Exit;
end;

// Add a new Workbook, Neue Arbeitsmappe offnen
ExcelApp.Workbooks.Add(xlWBatWorkSheet);

// Open a Workbook, Arbeitsmappe offnen
ExcelApp.Workbooks.Open('c:\pasta1.xls');

// Rename the active Sheet
ExcelApp.ActiveSheet.Name := 'Pasta1';

// Rename
ExcelApp.Workbooks[1].WorkSheets[1].Name := 'Pasta1';

// Insert some Text in some Cells[Row,Col]
ExcelApp.Cells[1, 1].Value := 'Test';
ExcelApp.Cells[2, 1].Value := 'http://www.delphi3000.com';
ExcelApp.Cells[3, 1].Value := FormatDateTime('dd-mmm-yyyy', Now);

// Setting a row of data with one call
//ExcelApp.Range['A2', 'D2'].Value := VarArrayOf([1, 10, 100, 1000]);

// Setting a formula
// ExcelApp.Range['A11', 'A11'].Formula := '=Sum(A1:A10)';

// Change Cell Alignement
// ExcelApp.Cells[2, 1].HorizontalAlignment := xlright;

// Change the Column Width.
ColumnRange := ExcelApp.Workbooks[1].WorkSheets[1].Columns;
ColumnRange.Columns[1].ColumnWidth := 20;
ColumnRange.Columns[2].ColumnWidth := 40;

// Change Rowheight / Zeilenhohe andern:
ExcelApp.Rows[1].RowHeight := 15.75;

// Merge cells, Zellen verbinden:
ExcelApp.Range['B3:D3'].Mergecells := True;

// Apply borders to cells, Zellen umrahmen:
ExcelApp.Range['A14:M14'].Borders.Weight := xlThick; // Think line/ Dicke Linie
ExcelApp.Range['A14:M14'].Borders.Weight := xlThin; // Thin line Dunne Linie

// Set Bold Font in cells, Fettdruck in den Zellen

ExcelApp.Range['B16:M26'].Font.Bold := True;

// Set Font Size, Schriftgro?e setzen
ExcelApp.Range['B16:M26'].Font.Size := 12;

//right-aligned Text, rechtsbundige Textausrichtung
ExcelApp.Cells[9, 6].HorizontalAlignment := xlright;

// horizontal-aligned text, horizontale Zentrierung
ExcelApp.Range['B14:M26'].HorizontalAlignment := xlHAlignCenter;

// left-aligned Text, vertikale Zentrierung
// ExcelApp.Range['B14:M26'].VerticallyAlignment := xlVAlignCenter;

{ Page Setup }

ExcelApp.ActiveSheet.PageSetup.Orientation := xlLandscape;

// Left, Right Margin (Seitenrander)
ExcelApp.ActiveSheet.PageSetup.LeftMargin := 35;
ExcelApp.ActiveSheet.PageSetup.RightMargin := -15;

// Set Footer Margin
ExcelApp.ActiveSheet.PageSetup.FooterMargin := ExcelApp.InchesToPoints(0);

// Fit to X page(s) wide by Y tall
ExcelApp.ActiveSheet.PageSetup.FitToPagesWide := 1; // Y
ExcelApp.ActiveSheet.PageSetup.FitToPagesTall := 3; // Y

// Zoom
ExcelApp.ActiveSheet.PageSetup.Zoom := 95;

// Set Paper Size:
// ExcelApp.PageSetup.PaperSize := xlPaperA4;

// Show/Hide Gridlines:
ExcelApp.ActiveWindow.DisplayGridlines := False;

// Set Black & White
ExcelApp.ActiveSheet.PageSetup.BlackAndWhite := False;

// footers
ExcelApp.ActiveSheet.PageSetup.RightFooter := 'Right Footer / Rechte Fu?zeile';
ExcelApp.ActiveSheet.PageSetup.LeftFooter := 'Left Footer / Linke Fu?zeile';

// Show Excel Version:
ShowMessage(Format('Excel Version %s: ', [ExcelApp.Version]));

// Show Excel:
// ExcelApp.Visible := True;

// Save the Workbook
//ExcelApp.SaveAs('c:\filename.xls');

// Save the active Workbook:
// ExcelApp.ActiveSheet.Protect.Password := 'Teste';
ExcelApp.ActiveSheet.Protect(Password:='Teste', DrawingObjects:=True, Contents:=True, Scenarios:=True);//;
//Contents:=True, Scenarios:=True
ExcelApp.ActiveWorkBook.SaveAs('c:\filename.xls');
end;

procedure TForm1.FormDestroy(Sender: TObject);
begin
// Quit Excel
if not VarIsEmpty(ExcelApp) then
begin
ExcelApp.DisplayAlerts := False; // Discard unsaved files....
ExcelApp.Quit;
end;

end;

end.

How protect Excel Sheet using Delphi?

2009-07-26T22:53:00.001-07:00

How protect Excel Sheet using Delphi?

2009-07-26T22:53:00.000-07:00

BORLAND DELPHI 7 TUTORIAL - FOR WINDOWS - TUTORIAL GUIDE HELP FREE

2009-07-24T19:38:00.000-07:00

FREE DOWNLOAD THIS TUTORIAL
This tutorial in pdf format so you can save it to your computer or print.

Here you leave the free download of the tutorial
Nota: The tutorial you are about to download is compressed format . rar, if you do not have a decompressor rar files you can download free 7-zip and to display the Foxit PDF Reader.

CONTENTS BORLAND DELPHI 7 TUTORIAL - FOR WINDOWS

Component Writer’s Guide
Borland Delphi 7 for Windows
Chapter 1
Overview of component creation 1-1
Class library
Components and classes
Creating components
Modifying existing controls
Creating windowed controls
Creating graphic controls
Subclassing Windows controls
Creating nonvisual components
What goes into a component?
Removing dependencies
Setting properties, methods, and events
Properties
Methods
Events
Encapsulating graphics
Registering components
Creating a new component
Creating a component with the
Component wizard
Creating a component manually
Creating a unit file
Deriving the component
Registering the component
Creating a bitmap for a component
Installing a component on the Component palette
Making source files available
Testing uninstalled components
Testing installed components
Delphi 7 Tutorial
Good tutorials pdf
Software user guide
Manuals free
Help me programming
Bible Borland
Table of Contents
Chapter 2
Object-oriented programming for component writers
Defining new classes
Deriving new classes
To change class defaults to avoid repetition
To add new capabilities to a class
Declaring a new component class
Ancestors, descendants, and class hierarchies
Controlling access
Hiding implementation details
Defining the component writer’s interface
Defining the runtime interface
Defining the design-time interface
Dispatching methods
Static methods
An example of static methods
Virtual methods
Overriding methods
Dynamic methods
Abstract class members
Classes and pointers
Chapter 3
Creating properties
Why create properties?
Types of properties
Publishing inherited properties
Defining properties
Property declarations
Internal data storage
Direct access
Access methods
The read method
The write method
Default property values
Specifying no default value
Creating array properties
Creating properties for subcomponents
Creating properties for interfaces
Storing and loading properties
Using the store-and-load mechanism
Specifying default values
Determining what to store
Initializing after loading
Storing and loading unpublished properties
Creating methods to store and load property values
Overriding the DefineProperties method
Chapter 4
Creating events
What are events?
Events are method pointers
Events are properties
Event types are method-pointer types
Event-handler types are procedures
Event handlers are optional
Implementing the standard events
Identifying standard events
Standard events for all controls
Standard events for standard controls
Making events visible
Changing the standard event handling
Defining your own events
Triggering the event
Two kinds of events
Defining the handler type
Simple notifications
Event-specific handlers
Returning information from the handler
Declaring the event
Event names start with “On”
Calling the event
Chapter 5
Creating methods
Avoiding dependencies
Naming methods
Protecting methods
Methods that should be public
Methods that should be protected
Abstract methods
Making methods virtual
Declaring methods
Chapter 6
Using graphics in components
Overview of graphics
Using the canvas
Working with pictures
Using a picture, graphic, or canvas
Loading and storing graphics
Handling palettes
Specifying a palette for a control
Off-screen bitmaps
Creating and managing off-screen bitmaps
Copying bitmapped images
Responding to changes
Chapter 7
Handling messages and system notifications
Understanding the message-handling system
What’s in a Windows message?
Dispatching messages
Tracing the flow of messages
Changing message handling
Overriding the handler method
Using message parameters
Trapping messages
Creating new message handlers
Defining your own messages
Declaring a message identifier
Declaring a message-record type
Declaring a new message-handling method
Sending messages
Broadcasting a message to all controls in a form
Calling a control’s message handler directly
Sending a message using the Windows message queue
Sending a message that does not execute immediately
Responding to system notifications using CLX
Responding to signals
Assigning custom signal handlers
Responding to system events
Commonly used events
Overriding the EventFilter method
Generating Qt events
Chapter 8
Making components available at design time
Registering components
Declaring the Register procedure
Writing the Register procedure
Specifying the components
Specifying the palette page
Using the RegisterComponents function
Providing Help for your component
Creating the Help file
Creating the entries
Making component Help context-sensitive
Adding component Help files
Adding property editors
Deriving a property-editor class
Editing the property as text
Displaying the property value
Setting the property value
Editing the property as a whole
Specifying editor attributes
Registering the property editor
Property categories
Registering one property at a time
Registering multiple properties at once
Specifying property categories
Using the IsPropertyInCategory function
Adding component editors
Adding items to the context menu
Specifying menu items
Implementing commands
Changing the double-click behavior
Adding clipboard formats
Registering the component editor
Compiling components into packages
Chapter 9
Modifying an existing component
Creating and registering the component
Modifying the component class
Overriding the constructor
Specifying the new default property value
Chapter 10
Creating a graphic control
Creating and registering the component
Publishing inherited properties
Adding graphic capabilities
Determining what to draw
Declaring the property type
Declaring the property
Writing the implementation method
Overriding the constructor and destructor
Changing default property values
Publishing the pen and brush
Declaring the class fields
Declaring the access properties
Initializing owned classes
Setting owned classes’ properties
Drawing the component image
Refining the shape drawing
Chapter 11
Customizing a grid
Creating and registering the component
Publishing inherited properties
Changing initial values
Resizing the cells
Filling in the cells
Tracking the date
Storing the internal date
Accessing the day, month, and year
Generating the day numbers
Selecting the current day
Navigating months and years
Navigating days
Moving the selection
Providing an OnChange event
Excluding blank cells
Chapter 12
Making a control data aware
Creating a data browsing control
Creating and registering the component
Making the control read-only
Adding the ReadOnly property
Allowing needed updates
Adding the data link
Declaring the class field
Declaring the access properties
An example of declaring access properties
Initializing the data link
Responding to data changes
Creating a data editing control
Changing the default value of FReadOnly
Handling mouse-down and key-down messages
Responding to mouse-down messages
Responding to key-down messages
Updating the field data link class
Modifying the Change method
Updating the dataset
Chapter 13
Making a dialog box a component
Defining the component interface
Creating and registering the component
Creating the component interface
Including the form unit
Adding interface properties
Adding the Execute method
Testing the component
Chapter 14
Extending the IDE
Overview of the Tools API
Writing a wizard class
Implementing the wizard interfaces
Installing the wizard package
Obtaining Tools API services
Using native IDE objects
Using the INTAServices interface
Adding an image to the image list
Adding an action to the action list
Deleting toolbar buttons
Debugging a wizard
Interface version numbers
Working with files and editors
Using module interfaces
Using editor interfaces
Creating forms and projects
Creating modules
Notifying a wizard of IDE events
Index
Tables
Component creation starting points
Levels of visibility within an object
How properties appear in the Object Inspector
Canvas capability summary
Image-copying methods
TWidgetControl protected methods for responding to system notifications
TWidgetControl protected methods for responding to events from controls
Predefined property-editor types
Methods for reading and writing property values
Property-editor attribute flags
Property categories
The four kinds of wizards
Tools API service interfaces
Notifier interfaces
Figures
Visual Component Library class hierarchy
Component wizard
Signal routing
System event routing

Using Delphi's Excel components

2009-07-22T22:53:00.000-07:00

Using Delphi's Excel components

The new Delphi 5 components make starting Excel very simple. Drop an ExcelApplication component on your form. If the AutoConnect property is true, Excel will start automatically when your program starts; if it's false, just call

  ExcelApplication1.Connect;

when you want to start Excel. To use a running instance of Excel, if there is one, set the ConnectKind property of TExcelApplication to ckRunningOrNew, or to ckRunningInstance if you don't want to start a new instance if Excel isn't running.

Once Excel has started, you can connect other components, such as TExcelWorkbook, using their ConnectTo methods:

  ExcelWorkbook1.ConnectTo(ExcelApplication1.ActiveWorkbook);
 ExcelWorksheet1.ConnectTo(ExcelApplication1.ActiveSheet as _Worksheet);
 ExcelWorksheet2.ConnectTo(ExcelApplication1.Worksheets.Item['Sheet2'] as _Worksheet);

Note that a workbook or worksheet must be open before you can connect to it! See How to open a workbook or How to create a workbook for code to do this.

I advise you not to try to start Excel using any component except the application component, however. At least on some setups, calling the Connect method (NB not the ConnectTo method!) of a Workbook or Worksheet component will cause an exception.

AnyDAC. Very High Performance using the Array DML

2009-02-15T04:29:00.000-08:00

AnyDAC encapsulates all database server specific implementation of the Array DML commands and lets you use identical code for all server types. Obviously, the resulting performance will differ based on the server implementation; especially Oracle, MS SQL Server and IBM DB2 have very powerful support of the Array DML and the resulting performance increase is just amazing.

Please use the sample code to get a feeling for the potential performance increase within your application and network.

Introduction
This tutorial has three main sections:

How to prepare your test environment.
The main elements of the Array DML commands.
The typical results of the Array DML test run.

Prepare your Test Environment
The following example works with the AnyDAC sample database environment. For further details about the installation of this database look into AnyDAC Demo Databases.

You find the demo projects in your sample directory:

This tutorial code - \Samples\Comp Layer\TADQuery\ExecSQL\AD03-ArrayDML or directly from article
A basic example code - \Samples\Comp Layer\TADQuery\ExecSQL\Batch.

How does the Array DML command work?
Imagine a "use case" where you have to INSERT, UPDATE, DELETE or run any other parametrized command N times, typically one command per single record. This means, that each set of input parameters requests to execute a SQL command and is transferred separately between the client and the server. This leads to a heavy load on the network, client and server.

Array DML allows you to transport not only one, but N-sets of data within one transfer. Have a look at the following example:


ADQuery1.SQL.Text:= 'insert into ADQA_Batch_test (tint, tstring) values(:f1, :f2)';

You can speed up your code dramatically by using Array DML commands. Such commands transfer not only one, but N sets of parameters.


ADQuery1.Params.ArraySize := 100;
...
for i := 0 to ADQuery1.Params.ArraySize do begin
 ADQuery1.Params[0].AsIntegers[i] := i;
 ADQuery1.Params[1].AsStrings[i] := 'Test' + IntToStr(i);
end;
ADQuery1.Execute(ADQuery1.Params.ArraySize);

This means the Params property of the query is no more a one- but a two-dimensional array, that allows you to store N sets of parameter values before sending them to the server.

Usage Hints:
Can be used for any SQL command that uses parameters (INSERT, UPDATE, DELETE ...).
The error handling is supported on record level and described in a separate article.
AnyDAC unifies the Array DML for different server types (no need for you do dig into the API).

Typical Results of the Array DML Test Run
The attached test code allows you to experiment within your specific environment.

Results of the test example can differ a lot depending on host and network performance. A typical picture of a local Oracle on a rather old laptop will still show > 100'000 records per second as you can see in this screen shot:

A larger Array DML ArraySize results in a higher performance (in our case up to a factor of 2000). We expect that the performance boost in your own environment will surprise you as well.

Performance Hints: Array DML command performance is influenced by:
The fact that they are a lot faster on slow networks as these commands create less TCP/IP packages.
They reduce the CPU load on the client side, as most of the time the server has to work on the array command.
The theoretical speed of > 100'000 rec/sec is not often reached as the server normally has to evaluate triggers and indexes.
For real large batch inserts (e.g. > 1'000'000 records), you should consider to drop and recreate non primary key indexes to reach a maximum performance.

Written by Dmitry Arefiev

Fast Report. Grouping

2009-02-11T04:32:00.001-08:00

In continuation of the topic on practical use of Fast Report components in complex programmes for billing, I will show you several practical examples of using grouping. For these examples I will use the payroll described in the first article 'First step in inheritance'. Reminding that a simplified form of the table has this appearance:

Synthetic key (PK)
Pay period
Payer’s code
Payer’s name
Kind of payment (FK)
Payment’s documents (FK)
Date of payments
Total payment
Type of service (FK)

Among other things, report clients want to have a list of payments for a period, for which, the user can have the possibility to order grouping in form of payment, in form of payer’s document, in form of payments and documents, and finally, totally without grouping (in actual fact, a lot of parameters are needed for ordering, but describing the technical work of other parameters is not important). Titles and columns for all the four reports are the same, therefore, we will need one report template with two groups. Together with these groups we will be determining the table’s features.
For creating the report 'Payers list' click menu File+New…, we move to the tab 'Template' and choose basic report BaseReport (its creation has been described in the first article) and we click the flag 'Inherit the report'. In the received report, there is already one inherited group — it will be grouped in form of payments. We again add one more group of payer’s documents. The second group will be immediately by default put inside the first. When needed, the groups can change places; drag the second group with a mouse above the first, but for our report there is no need to do this.
Further, according to documentation (UserManual-ru, chap 3.1) compulsory requirement for a report with grouping is SQL inquiry with sorting of grouped fields.
A ready report has the following appearance:

On the order form report there are two flags 'Grouping in form of payments', 'Grouping in form of payer’s document' which work independent of each other.

Activation/deactivation of visibility of the group header and group footer is done with the help of the property Visible. With the method FMainReport.FindObject we will find a pointer to the title of the group and set its property Visible in accordance with the flags on the order form .We do the same as well with group basement. Then we change the line ORDER BY in SQL text. If the user had set the flag 'Kind of payment' only, then sorting must start with the field 'Form of payment' , If set only 'Payer’s document', then with the field 'Payer’s document', but if set both flags - then sorting is needed on both fields.
When working with inserted groups, there can arise need to exclude field from the SQL query (for example, when using GROUP BY), on which one of the groupings in the report is done. For example, the client can be interested in the overall sum of every subscriber in form of payment. Then there is need to group on the dates of payment by the subscriber, so that we can get one line if the subscriber has more than one payment in a day.
In this case, to activate grouping, it’s not enough to just assign False the property Visible. If such a report is run, then we will get a mistake:

Setting the property Visible:= False does not change the execution of the expression described in the property Condition, but there is a call to a non-existent field in the SQL query. The mistake can be corrected if the property Condition is assigned the value of any constant, for example 1.
For increasing the usability of the report we use one more feature of Fast Report — Dynamic groups.
Our client has already valued the comfort ability of such an interactive report, that is, when the group opens/closes by clicking the mouse on the group title in the preview window.
The main problem when using dynamic group arises during calculation of each group’s sum. I has used several variants of calculating sum:

The easiest variant. Nothing changes either in the header or in the footer of the dynamic group. In this case, when turning, the header and the footer will be seen. I practically don’t use this variant, because the clearness of such a report is low, in my opinion.
The most accurate variant. Sum of a group is printed in the title of the group. In this case if no additional action is taken, and then when running the report, the sum will be equal to zero. There are two exits — create special SQL query for calculating the sum or execute the report in two passes, that is setting the property frxMainReport.ExgineOptions.DoublePass:= True. In any case, for this variant you need to change the report template. Remove group footer, that is (Visible:= False), and place sum in the group title .Am always faced with the fact that users are not always comfortable with seeing the sum in front of the group. That’s where the third variant appears.
Not very beautiful variant, but, strangely, it’s the one used most by the end users. When close the group, you need to hide the label 'Total per group' in the footer.
```
procedure grMainFooterOnBeforePrint(Sender: TfrxComponent);
begin
 if mdMainDetail.Visible then
   Memo16.Text:= 'Total '+ < class="st0">'NAME_FULL'>
 else
   Memo16.Text := '';
end;
```
This type of report will have the following appearance (when close the groups):In this variant the problem of sum per group arises. If the sum is considered in any ordinary way, SUM (), then, when running the value will be equal to 0. In order to calculate the sum in a closed group, we need to write the following SUM (, mdMainDetail, 1), where 1 – considering invisible mdMainDetail.
The most difficult variant. This combination 2 and 3, that is, when opening the group the sum will be shown in footer and hidden in the header, but when closing the group, footer completely hides and sum is shown in the header. In my practical, it is always enough to use the third variant.

I think, using group is very comfortable and flexible, because the number of nested levels is not limited. This facility allows building several like reports with help of simple controlling of group using one template.
Written by Irina Tsybulnikova

How to create a non-rectangular control

2009-02-11T04:05:00.000-08:00

You can create any controls with any shapes....HOW? I'LL tell you...

First of all you should specify the shape ( better to say specify the region)

To do this you can use one of the region functions, some of them are
ordered bellow.

CreateEllipticRgn
CreateEllipticRgnIndirect
CreatePolygonRgn
CreatePolyPolygonRgn
CreateRectRgn
CreateRectRgnIndirect
CreateRoundRectRgn
....
....

after using one of these functions you have a particular region.

the next step is assigning this region to the control you are working on.
This step is done using "setwindowrgn" function within the Formcreate Event.

This code makes a non-rectangular form for you, you can test it
to see the result:

procedure TForm1.FormCreate(Sender: TObject);
var points : array [1..5] of TPoint;
region : hrgn;
begin
points [1].x:= 10;
points [1].Y:= 10;
points [2].x:= 100;
points [2].y:= 50;
points [3].x:= 50;
points [3].y:= 80;
points [4].x:= 10;
points [4].y:= 200;
points [5].x:= 10;
points [5].Y:= 10;
region := createpolygonrgn(points, 5, 1);
setwindowrgn(form1.handle, region, true);
end;

Menampilkan progress-bar saat fetch data besar

2009-02-11T03:23:00.000-08:00

beberapa rekan banyak yg menanyakan, ada jg yg nanya via YM...

iseng2 daku explore event2 milik TADOQuery --> TADOConnection atau CodeGear menyebutnya DBGo pd Delphi2007 (BDS juga kali' ya)...

utk menampilkan progress-bar, anda bisa memanfaatkan event OnFetchProgress milik TADOQuery...

[pas:1:be702a67be]
unit Unit1;

interface

uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, DB, ADODB, StdCtrls, ComCtrls;

type
TForm1 = class(TForm)
ADOConnection1: TADOConnection;
ADOQuery1: TADOQuery;
ProgressBar1: TProgressBar;
Label1: TLabel;
procedure ADOQuery1FetchProgress(DataSet: TCustomADODataSet; Progress,
MaxProgress: Integer; var EventStatus: TEventStatus);
procedure ADOQuery1FetchComplete(DataSet: TCustomADODataSet;
const Error: Error; var EventStatus: TEventStatus);
private
{ Private declarations }
public
{ Public declarations }
end;

var
Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.ADOQuery1FetchComplete(DataSet: TCustomADODataSet;
const Error: Error; var EventStatus: TEventStatus);
begin
if EventStatus <> esOK then
MessageDlg(Format('Source: %s%sDesc: %s', [Error.Source, #13#10, Error.Description]), mtError, [mbOK], 0);
Close;
end;

procedure TForm1.ADOQuery1FetchProgress(DataSet: TCustomADODataSet; Progress,
MaxProgress: Integer; var EventStatus: TEventStatus);
begin
if EventStatus = esOK then
begin
ProgressBar1.Max:= MaxProgress;
ProgressBar1.Position:= Progress;
end;
Application.ProcessMessages;
end;

end.
[/pas:1:be702a67be]

btw.. bagaimana efek dari penggunaan event onFetchProgress atau sejenis.. apakah ada penurunan performance (performance penalty)? dan seberapa besar?
saya belum mencoba hal ini di ADO, tapi hal serupa juga disediakan oleh komponen middleware yg sedag daku pake, dan terdapat penurunan performance, walaupun tidak besar.

Tapi saya rasa untuk data besar, jika penalty tersebut cukup kecil, tidak mengapa, karena tujuannya lebih ke 'visual feedback'.

Kalau saya sih dah tahu sejak lama......
tapi hati2 dalam penggunaan onfetchProgress
setahu saya untuk D7 hanya bisa digunakan pada ADODataset.
Kemudian untuk mendapatkan progress yang bagus, dataset jangan langsung dikoneksikan dengan Grid, lebih baik saat fetching di disconect, setelah fetching selesai baru dikoneksikan lagi datasetnya ke dbgrid.

Untuk mendapatkan performance yang bagus saat fetching, silahkan anda atur executeoptions-nya agar didapatkan fetching yang smooth

benar yg dikatakan sodara @EkoIndri...
TDataset telah menyediakan DisableControls & EnableControls utk men-disables data display in data-aware controls associated with the dataset.
tanpa perlu secara fisik men-disconnect dataset ke data-aware (DBGrid, DBEdit dll).

Async fetch of a dataset

2009-02-11T03:19:00.000-08:00

I'm actually using TsaBetterADODataSet, and I'm trying to do an asynchrouous
fetch of data using  an Execute option of eoAsyncFetchNonBlocking. I'm using
a CommandType of cmdText.  I'm trying to use the events FetchComplete, and
FetchProgress, but they never get called.  I've also set InitialFetchSize to
0 to
make sure they get called even for a small data set.  I've set breakpoints
in them, and the breakpoints never get called.  This is under Delphi 7.  Any
help would be appreciated.

-- Larry Maturo

"Initial Fetch size" needs to be set after the recordset is created but before
it opens.  AdoDataset providess an OnRecordSetCreate method to do that.
--
Brian Bushay

Okay,  the OnRecordSetCreate event gets triggered, I set the "Initial Fetch
size", and nothing changes.  FetchComplete and FetchProgress still don't get
called. Any other ideas?

SET ExecuteOptions to EoAsyncFetchNonblocking
No other changes to the default properties
write your OnfetchProgress event to monitor records returned.
That is all there is to it


-- Larry Maturo

Barcodes and Delphi

2009-02-11T03:12:00.000-08:00

Barcodes generally consist of a series of alternately black and white bars, of varying width. The pattern is defined by encoding the data the barcode represents, using a set of pre-defined patterns and optionally additional mathematical operations to condense the data or add a check-digit.

The TBits class stores a series of bits, in the smallest possible size of memory. It is an ideal object to store encoded data in one of the many barcode-formats, and use in one of many ways to generate the barcode itself. For example:
- generate a monochrome bitmap,
- generate HTML to display the barcode (attention, generally background-color's don't get printed, use !important or a black border-left for a white span or td)
- generate printer-code to send to the printer directly
...

I've put up source-code that demonstrates this here:

http://yoy.be/barcode

Opening a Data Set & Showing Progress Bar

2009-02-11T02:56:00.000-08:00

Hallo
I want to exec querry in asynchronous mode because i want to have a
progressbar.
I have done that things yet:
ExecuteOption - eoAsynchFetch::=true
CacheSize:=16 Mac Records:=64 (->4 step in progessbar)
But it doesn,t work :(
What I Have to do more ?
Now, procedure OnFetchProgress is executed only one (not for 64/16)
I use ADOQuery.Active:=true
What with the rest of executeOtpions?
When i set eoAsyncExecute on true , appliaction reach the exception
Thanks for any help

Opening a Data Set & Showing Progress Bar
	Hi, How can I show a progress bar and add to it's position amount while I want to open a data set? I don't want to get the record count at first cause it takes the same time as opening the data set.

I've never used it before, but this was taken from the Borland Delphi Help File.

It's the OnFetchProgress event of a Dataset.

Occurs periodically during an asynchronous data retrieval operation.

TFetchProgressEvent = procedure(DataSet: TCustomADODataSet; Progress, MaxProgress: Integer; var EventStatus: TEventStatus) of object;
property OnFetchProgress: TfetchProgressEvent;

Description

Write an OnFetchProgress event handler to take specific action during an asynchronous data retrieval operation. The OnFetchProgress event fires periodically during the data retrieval to provide indications of its progress. Create a handler for this event to react to this periodic notification, such as providing the user with a visual indication of the progress of the data retrieval.

DataSet is the ADO dataset component that triggered the OnFetchProgress event. This dataset component also contains the recordset in question.

Progress is the number of records that have been received since the data fetching operation began.

MaxProgress is the total number of records to be retrieved by the operation.

Progress and MaxProgress used together to get percent complete. For example, Progress divided by MaxProgress and multiplied by 100 yields the percent completion of the data fetching.

procedure TForm1.ADODataSet1FetchProgress(DataSet: TCustomADODataSet; Progress, MaxProgress: Integer; var EventStatus: TEventStatus);
begin
Caption := 'Percent complete: ' +
IntToStr(Trunc(Progress / MaxProgress * 100)) + '%';
Application.ProcessMessages;
end;

Delhi & DotNET

2008-12-14T19:18:00.000-08:00

Delphi & Dotnet

Publish at Scribd or explore others: Web 2.0 Technology .net

Pictures inside a database Seeking the start of Jpeg in the BLOB

2008-12-14T17:52:00.000-08:00

OLE object type format - take three!
All this leaves us with nothing but to store the picture to a disk (as an ordinary binary file) and see what's inside it.
One nice thing with picture files (formats) is that all have some header that uniquely identifies the image. The JPG picture file starts with the, so called, SOI marker that has the value of $FFD8 hex.

This next line of code stores the value of the Picture field to a file (BlobImage.dat) in the working directory. Assign this code in the OnCreate event for the form, start the project and remove the code.

ADOTable1Picture.SaveToFile('BlobImage.dat');

Once we have the file, we can use some Hex editor to see it's content.

Would you believe this! MS Access stores the path of a linked OLE object as part of the object's definition in the OLE object field. Because the definition of OLE object storage is not documented (!? this is straight from MS) there is no way to know what gets written before the actual image data.

Think about this twice. First: we'll need to seek to the 'FFD8' and read the image from there. Second, the 'FFD8' might not always be at the same position in the file. Conclusion: we need a function that returns the position of the SOI marker for the JPG file stored as OLE object in an Access database.

The correct way - take four!
Provided with the Blob type field our function should return the position of the 'FFD8' string inside the ADOBlobStream. The ReadBuffer reads byte by byte from the stream. Each call to ReadBuffer moves the position of the stream by one. When two bytes together (as hex values) result in SOI marker the function returns the stream position. This is the function:

function JpegStartsInBlob
        (PicField:TBlobField):integer;
var
bS     : TADOBlobStream;
buffer : Word;
hx     : string;
begin
Result := -1;
bS := TADOBlobStream.Create(PicField, bmRead);
try
 while (Result = -1) and
       (bS.Position + 1 <>do
 begin
  bS.ReadBuffer(buffer, 1);
  hx:=IntToHex(buffer, 2);
  if hx = 'FF' then begin
    bS.ReadBuffer(buffer, 1);
    hx:=IntToHex(buffer, 2);
    if hx = 'D8' then Result := bS.Position - 2
    else if hx = 'FF' then
      bS.Position := bS.Position-1;
  end; //if
 end; //while
finally
 bS.Free
end;  //try
end;

Once we have the position of the SOI marker we use it to seek to it in the ADOBlob stream.

uses jpeg;
...
procedure TForm1.btnShowImageClick(Sender: TObject);
var
 bS  : TADOBlobStream;
 Pic : TJpegImage;
begin
 bS := TADOBlobStream.Create
       (AdoTable1Picture, bmRead);
 try
    bS.Seek(JpegStartsInBlob(AdoTable1Picture),
           soFromBeginning);
   Pic:=TJpegImage.Create;
   try
    Pic.LoadFromStream(bS);
    ADOImage.Picture.Graphic:=Pic;
   finally
    Pic.Free;
   end;
 finally
   bS.Free
 end;
end;

Run the project and voila!

Who can now say that programming isn't FUN?

Note: in real code application we would have the code to read and display the image from the current row in the AfterScroll event of a TDataSet (that is in the ADOTable1AfterScroll event procedure). AfterScroll occurs after an application scrolls from one record to another.

Take five!
That's it for this chapter. You can now store and display all your favorite JPG pictures. In the last page of this article I have provided you with the entire code (form1's unit); all the data assignment is placed in the OnCreate event of the form. This ensures that all three components are correctly linked - you don't need to use the Object Inspector at design-time.
I agree, the chapter was not designed for beginners, but hey the World is cruel. Another thing: did you mentioned that at the end you don't know how to change (or add some new) picture in a table! We'll, that's whole another story!

Hm, ok I give up! Take a look at the code ... see the "SaveJpegToTable" procedure? This one does the job of placing a picture inside a database.

Pictures inside a database Pulling the Jpeg with DBImage - the wrong way

2008-12-14T17:47:00.000-08:00

The DBImage - take one
The first thing I do when trying to do something new with Delphi is to "ask" Delphi Help for help. This is what the Help system replies: TDBImage (Data Controls page on the component palette) represents a graphic image from a BLOB (binary large object) field of the current record of a dataset. Use TDBImage to represent the value of graphic fields. TDBImage allows a form to display graphical data from a dataset. The DBImage is nothing more than a TImage component with some data aware properties. The two most important ones are: DataSource and Field. The DataSource property links the image component to a dataset. We have a DataSoure component named DataSource1 on our form that represent a dataset. The Field property indicates the field (in a table) that holds the image.

All clear, put a DBImage on form and leave the DBImage1 name. To actually link a DBImage with a BLOB field in a Table we simply need to do the following assignment (using the Object Inspector):

DBImage1.DataSource = DataSource1
DBImage1.Field = Picture

This should do the trick of displaying the JPEG image stored in the Picture field of the Applications table.

To see whether this assignment will work the only thing we have to do is to set the Active property of the ADOTable1 component to True. We can do this at design time with the Object Inspector. Once you set it you'll get the following:

Now what? Why does it say "Bitmap image is not valid." We have a JPEG picture not the BMP - is this the problem? Let's go back to the Help.

After a few clicks through the Help the conclusion is: to get the JPG inside a database we need to use the TJpegImage object. To display the picture we need the simple, non-data aware, version of the Image component. Even more we'll need to use streams to load a picture from a BLOB object. The Help states that we should use TADOBlobStream to access or modify the value of a BLOB or memo field in an ADO dataset.

Pictures inside a database

2008-12-14T17:19:00.000-08:00

Working with BLOBs. Storing pictures in Access.
These days developing database applications requires more than just operating with textual or numeric data. If you are, for example, developing an Internet/intranet or multimedia based application, frequently there is a need to display pictures along with text from a database.

In this third chapter of the Delphi database course, we'll see how to pull out and display the graphical data (images) inside an Access database with ADO. Don't be worried with the fact that working with images inside an Access database requires more database programming skills than this course has provided so far. Let's pretend that we know more to get more.

If you have followed this course from the beginning (specially the second chapter), you know how to connect to a database and display the Applications (from our working aboutdelphi.mdb database) table in a DBGrid. Remember, we used 3 data components: DBGrid, ADOTable and DataSource to get and display the data from the Applications table.
Back in the first chapter when we created our database, the last filed in the Applications table was left blank (after filling our database with some dummy data). The last field has the name Picture and is of the OLE object type.

If you scroll right to the last column of the DBGrid you'll see something like:

Blob in DBGrid

When using MS Access, we can store images (and other large data objects such as sound or video) in a field that has the OLE object type. This type of data is referred to as a Binary Large Object Bitmap (BLOB).

Naturally when working with images, several types of picture formats are available. The most commonly used include JPEG, GIF and BMP. JPEG format has proven to be widely accepted by Web masters because of the small amount of storage required (in other words JPEGs are smaller than BMPs in bytes).

Delphi, of course, has means of handling BMP, GIF and JPEG graphic formats. The rest of this article will deal with JPEG file formats.

Storing pictures in Access
Before going on to discussion about displaying the image inside a table within a Delphi form, we need to add some graphical data to our database.

Start Access and open the aboutdelphi.mdb database. Open the Applications table (it should have one row of data) and select the Picture field.

A table in Access

To add an image do the following:

1. Select Insert|Object... this will display the Insert Object dialog box.

MS Access...Insert Object

2. Click on the Browse button, this pops up the Browse open dialog. Note: you probably have some .jpg files on your computer, so you could use those, or if you have Win 98 and newer, MS Paint will save pictures in this format, as will many other programs. Navigate to a directory where your pictures are stored and select one.

Note: the text in the Picture field holds the name of an executable used to work with JPEG files on your computer. Of course you don't see the picture in a table grid. To actually see the graphics double click that field. This will load the image within the JPG type associated application.

Now, when we have a picture inside a database, let's see how to display it inside a Delphi form. We already have a Delphi form with data components on it from the second chapter of this course.

Countering Delphi Techniques

2008-12-14T17:00:00.000-08:00

Countering Delphi Techniques

Publish at Scribd or explore others: Activism Politics children college

Displaying Macromedia Flash .SWF files in your Delphi Application

2008-12-11T04:08:00.000-08:00

If you have considered using your Macromedia Flash files to help add some flavor to your Delphi applications, but never knew how, this article is for you.

Download demo project

First of all you must find the file titled

"SWFLASH.OCX" usually in the C:\Windows\System\Macromed\Flash directory.

You can then in Delphi click on the menu Component --> Import ActiveX Control. Choose the SWFlash.OCX file and import it. Once you install it, you will then have the TShockWaveFlash component to drag onto your form.

PROBLEM: The important thing to remember is that if deploy your application then they must have this OCX file or it will not run.

SOLUTION: To keep your program simple and only have 1 file to distribute, I would suggest to create a resource file of the OCX and include in your .EXE. Extract the file if needed and register it. I have included some sample code on how to do this.

CREATING RESOURCE FILE: (Skip this section if you already understand it). Create a new Text File in Notepad. Type the following line:

Flash RCDATA "SWFLASH.OCX"

Make sure the text file is saved as Filename.rc, I saved mine as FlashOCX.rc. You must also have the .rc file in the same directory as the SWFLASH.OCX file in order for this to work.

Open your command prompt (DOS window) and find the brcc32.exe file in your bin directory wherever you installed Delphi. Type this and execute it in DOS:

Brcc32 DirofFile\FlashOCX.rc
Example: Brcc32 c:\windows\system\flashocx.rc

It should now have created a file titled "FLASHOCX.RES". You can now include this into your application.

{$R *.RES}
{$R FLASHOCX.RES}

The R Directive tells your program to include that Resource File.

HOW TO EXTRACT AND REGISTER:

First off we need to check to see if we can play the Flash File or not. Click on Project --> View Source (in Delphi 5) and pull up the project source code. We want to check for the EOleSysError Message when creating the first form. If we encounter the error, then we know we must register the OCX on that particular machine.

uses comobj

begin
Application.Initialize;
try
Application.CreateForm(TForm1, Form1);
except
On EOleSysError Do
begin
//Register OCX File because not found.
end;
end;
Application.Run;
end.

This next bit of source code that I will display will give you what is needed to extract the resource file and place into the Windows System Directory.

uses
windows, classes, sysutils

var
aSystemDirZ : array[0..2047] of Char;
fSystemDir : String;

...

GetSystemDirectory ( aSystemDirZ, 2047 );
fSystemDir := aSystemDirZ;

ResStream := TResourceStream.Create(0, 'Flash', RT_RCDATA);
try
FileStream := TFileStream.Create(fSystemDir+'SWFLASH.OCX', fmCreate);
try
FileStream.CopyFrom(ResStream, 0);
finally
FileStream.Free;
end;
finally
ResStream.Free;
end;

ENTIRE CODE:

You must still register the OCX file, and I will now display the entire code so you can see how it would all fit together.

program FlashPlayer;

uses
 Forms, Dialogs, comobj, windows, classes, sysutils,
 uMain in 'uMain.pas' {Form1};

{$R *.RES}
{$R FLASHOCX.RES}

type
 TRegFunc = function : HResult; stdcall;

function WinExecAndWait32( FileName: String; Visibility  : Integer ) : Cardinal;
var >{ by Pat Ritchey }
   zAppName     : array[0..512] of char;
   zCurDir      : array[0..255] of char;
   WorkDir      : String;
   StartupInfo  : TStartupInfo;
   ProcessInfo  : TProcessInformation;
begin
   StrPCopy( zAppName, FileName );
   GetDir  ( 0,        WorkDir  );
   StrPCopy( zCurDir,  WorkDir  );

   FillChar( StartupInfo, Sizeof( StartupInfo ), #0 );

   StartupInfo.cb          := Sizeof( StartupInfo );
   StartupInfo.dwFlags     := STARTF_USESHOWWINDOW;
   StartupInfo.wShowWindow := Visibility;

   if ( not CreateProcess( nil,
                           zAppName, { pointer to command line string }
                           nil, { pointer to process security attributes }
                           nil, { pointer to thread security attributes }
                           false, { handle inheritance flag }
                           CREATE_NEW_CONSOLE or { creation flags }
                           NORMAL_PRIORITY_CLASS,
                           nil, { pointer to new environment block }
                           zCurDir, { pointer to current directory name }
                           StartupInfo, { pointer to STARTUPINFO }
                           ProcessInfo ) ) then
   begin
       Result := $FFFFFFFF; { pointer to PROCESS_INF }
       MessageBox( Application.Handle, PChar( SysErrorMessage( GetLastError ) ), 'Yipes!', 0 );
   end
   else
   begin
       WaitforSingleObject( ProcessInfo.hProcess, INFINITE );
       GetExitCodeProcess ( ProcessInfo.hProcess, Result   );
       CloseHandle        ( ProcessInfo.hProcess           );
       CloseHandle        ( ProcessInfo.hThread            );
   end;
end;

var
 aSystemDirZ : array[0..2047] of Char;
 aShortPath  : array[0..2047] of Char;
 fSystemDir  : String;
 aCommand    : String;
 aHandle     : Cardinal;
 aFunc       : TRegFunc;
 ResStream   : TResourceStream;
 FileStream  : TFileStream;
begin

 GetSystemDirectory ( aSystemDirZ, 2047      );
 fSystemDir := aSystemDirZ;
 Application.Initialize;
 try
 Application.CreateForm(TForm1, Form1);
 except
   On EOleSysError Do
   begin
     ResStream := TResourceStream.Create(0, 'Flash', RT_RCDATA);
       try
         FileStream := TFileStream.Create(fSystemDir+'SWFLASH.OCX', fmCreate);
         try
           FileStream.CopyFrom(ResStream, 0);
         finally
           FileStream.Free;
         end;
       finally
         ResStream.Free;
       end;

     try
       {Register the OCX File}
       aHandle := LoadLibrary( PChar( fSystemDir+'SWFLASH.OCX' ) );
       if ( aHandle >= 32 ) then
       begin
           aFunc := GetProcAddress( aHandle, 'DllRegisterServer' );
           if ( Assigned( aFunc ) = TRUE ) then
           begin
               GetShortPathName( PChar( fSystemDir+'SWFLASH.OCX' ), aShortPath, 2047 );
               aCommand := Format( '%s
egsvr32.exe /s %s', [fSystemDir, aShortPath] );
               WinExecAndWait32( aCommand, SW_HIDE );
           end;
           FreeLibrary( aHandle );
       end;

       //Try Creating the Form Again
       try
         Application.CreateForm(TForm1, Form1);
       except
         ShowMessage('Unable to find Macromedia Shockwave Flash.');
       end;

     except
       ShowMessage('Unable to register Macromedia Shockwave Flash.');
     end;
       {End of Registering the OCX File}
   end;
 end;
 Application.Run;
end.

END OF PROJECT SOURCE

HOW TO USE ACTIVEX CONTROL:

Properties

ReadyState (get only) - 0=Loading, 1=Uninitialized, 2=Loaded, 3=Interactive, 4=Complete.

TotalFrames (get only) - Returns the total number of frames in the movie. This is not available until the movie has loaded. Wait for ReadyState = 4.

FrameNum (get or set) - The currently displayed frame of the movie. Setting this will advance or rewind the movie.

Playing (get or set) - True if the movie is currently playing, false if it is paused.

Quality (get or set) - The current rendering quality (0=Low, 1=High, 2=AutoLow, 3=AutoHigh). This is the same as the QUALITY parameter.

ScaleMode (get or set) - Scale mode (0=ShowAll, 1= NoBorder, 2 = ExactFit). This is the same as the SCALE parameter.

AlignMode (get or set) - The align mode consists of bit flags. (Left=+1, Right=+2, Top=+4, Bottom=+8). This is the same as the SALIGN parameter.

BackgroundColor (get or set) - Override the background color of a movie. An integer of the form red*65536+green*256+blue use -1 for the default movie color.

Loop (get or set) - True if the animation loops, false to play once. Same as the MOVIE parameter.

Movie (get or set) - The URL source for the Flash Player movie file. Setting this will load a new movie into the control. Same as the MOVIE parameter.

Methods

Play() - Start playing the animation.

Stop() - Stop playing the animation.

Back() - Go to the previous frame.

Forward() - Go to the next frame.

Rewind() - Go to the first frame.

SetZoomRect(int left, int top, int right, int bottom) - Zoom in on a rectangular area of the movie. Note that the units of the coordinates are in twips (1440 units per inch). To calculate a rectangle in Flash, set the ruler units to Points and multiply the coordinates by 20 to get TWIPS.

Zoom(int percent) - Zoom the view by a relative scale factor. Zoom(50) will double the size of the objects in the view. Zoom(200) will reduce the size of objects in the view by one half.

Pan(int x, int y, int mode) - Pan a zoomed in movie. The mode can be: 0 = pixels, 1 = % of window.

Events

OnProgress(int percent) - Generated as the Flash Player movie is downloading.

OnReadyStateChange(int state) - Generated when the ready state of the control changes. The possible states are 0=Loading, 1=Uninitialized, 2=Loaded, 3=Interactive, 4=Complete.

FSCommand(string command, string args) - This event is generated when a GetURL action is performed in the movie with a URL and the URL starts with "FSCommand:". The portion of the URL after the : is provided in command and the target is provided in args. This can be used to create a response to a frame or button action in the Shockwave Flash movie.

For further information see the Macromedia Flash Website

In order to include your Flash files into your Delphi Application, just type in the directory of the .SWF file, then make "Embed Movie" = True, and it will be included in your file and not look at the Movie parameter any longer.