Delphi in a Nutshell

Name

RunError Procedure

Syntax

procedure RunError(ErrorCode: Integer = 0);

Description

The RunError procedure halts the program with an error status. RunError is not a real procedure.

Tips and Tricks

• When a runtime error occurs, if ErrorProc is nil, Delphi calls RunError to print an error message and stop the program. In a GUI application, Delphi shows the error message in a dialog box. In a console application, Delphi prints the error message to the console.

• If you write your own ErrorProc procedure, you can call RunError to halt the program and display a brief error message, but most likely you will want your ErrorProc procedure to do something different, such as raise an exception or print a different error message.

• The ExitProc procedure and units’ finalization sections get to run before the program terminates.

• Like Halt, RunError is a quick way to terminate a program, but not usually the right way for a GUI application. Instead, you should close the main form to terminate the application.

Example

// Report a run-time error. The address of the call to RunError // is the error address. The address passed to ErrorProc is // the address of the call to ErrorProc, which is close to, // but not quite the same as, the address of the call to // RunError. You can adjust the value returned by Caller, // but that would be highly dependent on Delphi's code generator. procedure ReportError(ErrorCode: Integer); function Caller: Pointer; asm MOV EAX, [ESP] end; type TErrorProc = procedure(Code: Integer; ...