delphi - Why Application.OnException never runs?

Question

Problem summary: The method assigned to Application.OnException never runs when an unhandled exception occurs.

I create a blank project with only this unit and place a single button on Unit.dfm (this is based on an official example) :

// Unit1.pas
// *********

type
TForm1 = class(TForm)
    Button1: TButton;
    procedure FormCreate(Sender: TObject);
    procedure AppException(Sender: TObject; E: Exception);
    procedure Button1Click(Sender: TObject);
end;

var
Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.FormCreate(Sender: TObject);
begin
    Application.OnException := AppException;
end;

procedure TForm1.AppException(Sender: TObject; E: Exception);
begin
    Application.Terminate;
end;

procedure TForm1.Button1Click(Sender: TObject);
begin
    raise Exception.Create('Incorrect password entered');
end;

Then I set a breakpoint inside TForm1.AppException(). I run the program, click the button, an error dialog is shown saying "Incorrect password entered" but if I continue execution the breakpoint never breaks; the program doesn't Terminate like I asked it too. The program continues running and I can press the button again.

I tried the same code (adapted) in Delphi 7 but the same result is encountered.

Answer 1

The only rational explanation is the FormCreate is not executing. You need to assign it to the form's OnCreate event handler. Use the object inspector to do so.