DynaPDF Manual - Page 46

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Language Bindings

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returned. All internal used resources will be freed, there is no need to call FreePDF() manually

beforehand.

Example (Single threaded):

In the following example we use a simple message box inside the error callback function.

However, in a larger project it makes sense to output error messages into an error log or list

box. DynaPDF ignores non-fatal errors by default so that it is possible to continue, but you can

protocol each warning and errors during PDF creation.

unit Unit1;

interface

uses Windows, Messages, SysUtils, Classes, Controls, Forms, Dialogs,

StdCtrls, dynapdf; // Include the file dynapdf.pas to the unit

type

TForm1 = class(TForm)

Button1: TButton;

procedure Button1Click(Sender: TObject);

private

public

end;

var Form1: TForm1;

implementation

// First, we define our callback function that is called if an

// error occurred. Note: The calling convention is stdcall!

function ErrProc(const Data: Pointer; ErrCode: Integer; const

ErrMessage: PAnsiChar; ErrType: Integer): Integer; stdcall;

var s: String;

begin

s := Format('%s'#13'Abort processing?', [ErrMessage]);

if MessageDlg(s, mtError, [mbYes, mbNo], 0) = mrYes then

Result := -1 // break processing

else

Result := 0; // try to continue

end;

procedure TForm1.Button1Click(Sender: TObject);

var pdf: TPDF;

begin

pdf := nil;

try

pdf := TPDF.Create;

// set the error callback function first

pdf.SetOnErrorProc(nil, @ErrProc);

pdf.SetDocInfoA(diAuthor, 'Jens Boschulte');

pdf.SetDocInfoA(diCreator, 'Delphi sample project');

pdf.SetDocInfoA(diSubject, 'My first PDF file...');

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