结帐表格C＃

Question

Recently I had to edit my program code so that the form will close after creating a PDF. In FormClosing() there's a MessageBox.Show for closing or not, depending on the DialogResult . The problem is that when I try to Close() , it shows me the MessageBox , I need to close it without showing it. Thanks.

private void Form1_FormClosing(object sender, FormClosingEventArgs e)
{
    if (MessageBox.Show("Exit?", "Exit", MessageBoxButtons.YesNo) == DialogResult.No)
    {
        e.Cancel = true;
    }
}

private void btn_PdfCreate_CloseForm_Click(object sender, EventArgs e)
{
    showPDf();
    // close pdf but skip MessageBox
}

Answer 1

You can stop listening to the event like so

private void btn_PdfCreate_CloseForm_Click(object sender, EventArgs e)
{
    this.FormClosing -= Form1_FormClosing
    showPDf();
    Close();
}

Answer 2

You can use the CloseReason property of the FormClosingEventArgs :

private void Form1_FormClosing(object sender, FormClosingEventArgs e)
{
    if (e.ClosingReason == CloseReason.UserClosing && MessageBox.Show("Exit?", "Exit", MessageBoxButtons.YesNo) == DialogResult.No)
    {
        e.Cancel = true;
    }
}

Answer 3

Use e.ClosingReason to find out if the formClosing event was fired by the user's attempt to close the form, or by something else.

for further reading, go to MSDN: http://msdn.microsoft.com/en-us/library/system.windows.forms.formclosingeventargs.closereason(v=vs.110).aspx

Answer 4

You anyways want to close the form after pdf creation. So call Form's Dispose method just after pdf creation like below and no need of registering for the OnFormClosing event

private void btn_PdfCreate_CloseForm_Click(object sender, EventArgs e)
{
    showPDf();
    this.Dispose();
}