Vcl.Forms.TApplication.OnException

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Delphi

property OnException: TExceptionEvent read FOnException write FOnException;

C++

__property TExceptionEvent OnException = {read=FOnException, write=FOnException};

Properties

Type Visibility Source Unit Parent
event public
Vcl.Forms.pas
Vcl.Forms.hpp
Vcl.Forms TApplication

Description

Occurs when an unhandled exception occurs in the application.

Use OnException to change the default behavior that occurs when an exception is not handled by application code. The OnException event handler is called automatically in the HandleException method.

OnException only handles exceptions that occur during message processing. Exceptions that occur before or after the execution of the application's Run method do not generate OnException events.

If an exception passes through the try blocks in the application code, the application automatically calls the HandleException method. Unless the exception object is EAbort, HandleException calls the OnException handler, if one exists. Otherwise, it calls ShowException to display a message box indicating that an error occurred.

TExceptionEvent is the type of the OnException event. It points to a method that handles exceptions in the application. The Sender parameter is the object that raised the exception, and E is the exception object.

Note: You can also respond to this event using the TApplicationEvents component, which allows you to assign an event handler using the IDE.

See Also

Code Examples