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How to catch all exceptions?

I am trying to catch all errors, but Visual Studio in debug mode breaks execution and shows "Unhandled exception" message box. I was trying to manage Visual Studio settings (Debug->Exceptions and Tools->Options->Debuging) but it does not help to solve this.

Please help me to fix this.

#include <QtGui/QApplication>
#include <QMessageBox>
 
 
int main(int argc, char *argv[])
{
	try {
 
		int x = 0;
		int y = 4/x;
		return 1;
	}
	catch (std::exception& e) {
		QMessageBox::critical(NULL, QString("Error"),QString(e.what()));
	}
	catch (...) {
		
		QMessageBox::critical(NULL, QString("Error"),QString("Unknown error!"));
	}
 
}

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Infinity08

A division by zero is not a C++ exception. It's a hardware exception. You cannot catch it like that.

jkr

"Unhandled exception" here refers to a Win32 SEH exception, not a C++ Exception, see http://msdn.microsoft.com/en-us/library/ms680657.aspx ("Structured Exception Handling") on these. You can handle these like

#include <QtGui/QApplication>
#include <QMessageBox>
 
 
int main(int argc, char *argv[])
{
        __try { // <--- note the underscores
 
                int x = 0;
                int y = 4/x;
                return 1;
        }
        __except(1) {
 
                QMessageBox::critical(NULL, QString("Error"),QString("SEH Exception"));
        
        }
 
}

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jkr

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doitex

ASKER

jkr:

Seems "__try" can't be used with QT4 clases - see compiler error message below:

Cannot use __try in functions that require object unwinding

jkr

Ah, yes, I almost forgot that little catch - what is your exact code (since there are no classes in the above)? You might want to use the translator in this case or wrap your Objects in a function call, e.g.

        __try { 
 
                MyFunctionThatUsesQtClasses();
        }
        __except(1) {
 
                QMessageBox::critical(NULL, QString("Error"),QString("SEH Exception"));
        
        }

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doitex

ASKER

tnx jkr

Your solution works! I have found complete source for that:

http://www.thunderguy.com/semicolon/2002/08/15/visual-c-exception-handling/3/

doitex

ASKER

http://www.thunderguy.com/semicolon/2002/08/15/visual-c-exception-handling/3/