TdxReport.ExportToImage(TStream) Method

Exports report content to a stream in the current image export format (selected using the Report Designer dialog).

The default image export format is PNG (Portable Network Graphics).

Declaration

procedure ExportToImage(AStream: TStream);

Parameters

Name	Type	Description
AStream	TStream	The target stream.

Remarks

Call the ExportToImage procedure to export report content to a stream in the current image format.

The ExportTimeout property allows you to set a timeout interval (in milliseconds) for export operations. If the specified export timeout is reached, an exception is thrown.

Image Export Format Settings

The default image export format is Portable Network Graphics (PNG).

You can select any supported image format and configure its settings in the Report Designer dialog (Behavior | Export Options):

Code Example: Export Reports to Image Files

The following code example loads an XML-based report template (TdxReport.Layout) from a REPX file, populates the template with test data defined in a connection string, and exports the resulting report as a PNG image:

Delphi

uses
  dxReport,  // Declares the TdxReport component and related types
  dxBackend.ConnectionString.JSON;  // Declares the TdxBackendInMemoryJSONConnection component
// ...

procedure TMyForm.Button1Click(Sender: TObject);
var
  AJSONDataConnection: TdxBackendInMemoryJSONConnection;
  AReport: TdxReport;
  AFileStream: TFileStream;
begin
  AJSONDataConnection := TdxBackendInMemoryJSONConnection.Create(Self);
  try
    AJSONDataConnection.Name := 'JSONData';
    // Specify in-memory report data as a connection string
    AJSONDataConnection.ConnectionString :=
      'Json=''[{"id":1, "caption":"test1"},{"id":2, "caption":"test2"}]''';
    AReport := TdxReport.Create(Self);
    try
      AReport.ReportName := 'Report';
      AReport.Layout.LoadFromFile('Report.repx');  // Loads a report template
      AFileStream := TFileStream.Create('Report.png', fmOpenReadWrite);
      try
        AReport.ExportToImage(AFileStream);  // Exports the report in the default image export format (PNG)
      finally
        AFileStream.Free;
      end;
    finally
      AReport.Free;
    end;
  finally
    AJSONDataConnection.Free;
  end;
end;

C++

#include "dxReport.hpp"  // Declares the TdxReport component
#include "dxBackend.ConnectionString.JSON.hpp"  // Declares the TdxBackendInMemoryJSONConnection component

// Add the following linker directives to the corresponding CPP source file:
#pragma link "dxReport"  // Required for dxReport.hpp declarations
#if defined(_WIN64)  // Required to use dxBackend.ConnectionString.JSON.hpp declarations
  #pragma link "dxBackend.ConnectionString.JSON.o"
#else
  #pragma link "dxBackend.ConnectionString.JSON.obj"
// ...

void __fastcall TMyForm::Button1Click(TObject *Sender)
{
  TdxBackendInMemoryJSONConnection *AJSONDataConnection;
  TdxReport *AReport;
  TFileStream *AFileStream;
  AJSONDataConnection = new TdxBackendInMemoryJSONConnection(this);
  try
  {
    AJSONDataConnection->Name = "JSONData";
    // Specify in-memory report data as a connection string
    AJSONDataConnection->ConnectionString =
      "Json=\"\"[{\"id\":1, \"caption\":\"test1\"}, {\"id\":2, \"caption\":\"test2\"}]\"";
    AReport = new TdxReport(this);
    try
    {
      AReport->ReportName = "Report";
      AReport->Layout->LoadFromFile("Report.repx");  // Loads a report template
      AFileStream = new TFileStream('Report.png', fmOpenReadWrite);
      try
      {
        AReport->ExportToImage(AFileStream);  // Exports the report in the default image export format (PNG)
      }
      __finally
      {
        delete AFileStream;
      }
    }
    __finally
    {
        delete AReport;
    }
  }
  __finally
  {
    delete AJSONDataConnection;
  }
}

Related Compiled Demo

To see the report export functionality in action, run the Report Designer/Viewer demo in the VCL Demo Center installed with compiled DevExpress VCL demos. Select any demo in the sidebar on the left, click the Export button, and use any export option listed in the menu.

Download: Compiled VCL Demos

Tip

You can find full source code for the installed compiled Report demo in the following folder:

%PUBLIC%\Documents\DevExpress VCL Demos\MegaDemos\Product Demos\ExpressReports\

Other Export Methods

You can call the following procedures to export report content to a stream in other formats:

ExportTo

Exports report content to a stream in any supported format.

ExportToCSV

Exports report content to a stream in the comma-separated values (CSV) format.

ExportToDOCX

Exports report content to a stream as an Office OpenXML (DOCX) document.

ExportToHTML

Exports report content to a stream as an HTML document.

ExportToMHT

Exports report content to a stream as a MIME HTML (MHT) document.

ExportToPDF

Exports report content to a stream in PDF format.

ExportToRTF

Exports report content to a stream as an RTF-formatted string.

ExportToText

Exports report content to a stream as plain text.

ExportToXLS

Exports report content to a stream in Microsoft Excel® binary format (XLS).

ExportToXLSX

Exports report content to a stream in Office Open XML spreadsheet format (XLSX).