CODEWITHSUNDEEP
c#winformsvisual-studio-2010visual-studio-debugging
valsidalv
valsidalv

Reputation: 821

WinForm closes even after removing Close()

I'm encountering strange behaviour from my WinForms app in VS 2010. I launch a new form using straight-forward code:

MainDisplayForm.cs:

using (MyForm myForm = new MyForm())
{
    var result = myForm.ShowDialog();
    if (result == DialogResult.OK)
    {
        // do stuff
    }
}

I added a Cancel button to MyForm that displayed a confirmation MessageBox to the user and then called this.Close(). I later removed the this.Close() line because I added a dedicated Close button. However, whenever I press Cancel the instance of MyForm still closes!

MyForm.cs:

private void cmdCancel_Click(object sender, EventArgs e)
{
    DialogResult result = MessageBox.Show( ... )
    // clear the form if user really wants to quit

    // this.Close()
    // even after removing the above line, program still jumps to FormClosing
}

When I debug line-by-line after clicking on the Cancel button, the program flow just jumps to MyForm_FormClosing after it hits the end of cmdCancel_Click. I created a new button and set its click event to cmdCancel_Click and it did not close the form - so the problem is solved, but I am still wondering if this is just a bug, or something else? I also made sure to reset the DialogResult property of my Cancel button back to None (after changing it to Cancel before I introduced the dedicated Close button).

Upvotes: 0

Views: 103

Answers (1)

qbik
qbik

Reputation: 5908

When exiting the scope of 'using' statement, it calls 'myForm.Dispose()' (that's the whole point of 'using' - to make sure Dispose()is called). This in turn destroys 'myForm' instance, including closing the window.

Upvotes: 1

Related Questions