Hello,

I always hoped that the crashes that happen in my program, are because of bugs in the compiler, or in the libraries I use, and not because of my code...

Yesterday my wish came true:
1- Start a windows application project, using any .NET laguage.

2- call the function:

   Application.EnableVisualStyles(); 

in the beginning of the main function, this function will allow the windows in your projects to have windows XP style.

3- Add a ComboBox to the main form...(combobox1)

4- Add an event handler for the ComboBox:

  cmbobox1_SelectionChangeCommitted. 

5- inside this event handler, wirte the code of showing a form:

  Form frm = new Form();
           frm.ShowDialog();

6- try to run the project, and change the selection of your combobox, then trying to close the new form.... BANG:

 An unhandled exception of type 'System.Runtime.InteropServices.SEHException' occurred in system.windows.forms.dll 

Solution:
To avoid this, and if you really need to show a form in a selection changed event handler in Combobox:
1- create a function that calls frm.ShowDialog, or frm.Show.
2- create a delegate that can take this new function.
3- call the delegate using (BeginInvoke).

sample in c#:

 delegate void ComboDelegate();

void ComboSelectionAsync()
{
// calling the Show function goes in here
}

private void combobox1_SelectionChangeCommitted(object sender, System.EventArgs e)
{
      ComboDelegate d = new ComboDelegate(ComboSelectionAsync);
      combobox1.BeginInvoke(d);
}

hope you don't spend three hours trying to solve this, as it happend with me..

Assured,
But strangely enough, if you call any other common dialog (Like OpenFileDialog, ColorChooser or even a simple MessageBox), every thing seems to work fine, so they must be doing something that we're missing; I'll look into it

Wanna hear something funnier (since you like to blame the compilers, althougth this one about unmanaged C++ compiler), try compiling the folowing code in Release mode (i.e. with the optimizations turned on); and see if it even gives logical results (for entries like 10 then 5):

// Some includes that I can't write explicitly, because of the site security issues...
using namespace std;

int main()
{
	int iInt1=0;
	int iInt2=0;

	cin >> iInt1 >> iInt2;

	bool bBool1 = false;
	bool bBool2 = false;
	//cout << iInt1 << endl << iInt2 << endl;

	if (iInt1 != iInt2)
	{
		bBool2 = iInt2 < iInt1;
		bBool1 = iInt1 < iInt2;
	}

	cout << "The smaller number is" << endl;

	if (bBool1)
		cout << iInt1;
	else if (bBool2)
		cout << iInt2;
	else
		cout << "neither" << endl;

	return 0;
}

Long time no see,

Hello Abdo,

it's very wierd bug, I couldn't figure what's the problem of the compiled code???
maybe it has something to do with compiling the operator (<) in the release mode...


it's nice to contact you again...

Jawad Abu Zakhem.

التعليق على مشاركة Abdo Haji-Ali في Dec 5, 2005 20:58 :

> // Some includes that I can't write explicitly, because of the site security issues...

الآن يمكنك إدراج code يحوي أية محارف بدون قيود تقريباً...