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property OnException: TExceptionEvent read FOnException write FOnException;


__property Vcl::Forms::TExceptionEvent OnException = {read=FOnException, write=FOnException};


Type Visibility Source Unit Parent
event protected
Vcl.AppEvnts TCustomApplicationEvents


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 application's 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 an error occurred.

Note: Call the CancelDispatch method from an OnException event handler to prevent the application from forwarding the event to any other application events objects.

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Code Examples