how to ceate event_click for button with C# ? [modified]

[xingselex]

my code is here . what is the misstake ? it error when click on that button and message that "the object reference not set to an instand of an object". please give me some help void Button_Click(object sender, EventArgs e) { Button clickedButton = sender as Button ; if (clickedButton.Name == "Program") { MessageBox.Show("lkjd;lfjal;sdkjf;laksdjfl;jasd"); } else { MessageBox.Show("dddddddddddddddd"); } }

modified on Thursday, May 21, 2009 3:27 PM

[Luc Pattyn]

Hi, if that handler gets connected to an event of something other than a Button, then Button clickedButton = sender as Button ; will set clickedButton to null. You can take care of that by changing your code to:

...
if (clickedButton!=null && clickedButton.Name == "Program")
...

or by making absolutely sure only Buttons are being wired up to this handler. FWIW: the fact that the handler's name starts with "Button" is fine for readability but does not change the way the code works. :)

Luc Pattyn [Forum Guidelines] [My Articles]

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[Lost User]

Are you sure the Button you are clicking on is a Button (and not some other control).

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