为什么Application.OnException永远不会运行？ [英] Why Application.OnException never runs?

问题描述

问题摘要分配给 Application.OnException 的方法在未处理的异常发生时永远不会运行。

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

我创建一个只有这个单元的空白项目，并在 Unit.dfm 上放置一个按钮（这是基于一个官方示例）：

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;

然后我在中设置断点TForm1.AppException（）。我运行程序，点击按钮，出现一个错误对话框，显示输入错误的密码，但如果我继续执行，断点不会中断;程序不是终止就像我也问过。程序继续运行，我可以再次按下按钮。

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.

我在Delphi 7中尝试了相同的代码（改编），但遇到相同的结果。

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

推荐答案

唯一理性的解释是 FormCreate 不执行。您需要将其分配给窗体的 OnCreate 事件处理程序。使用对象检查器这样做。

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.

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