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POObject Reference Not Set
 

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    <p>There are similar questions around here but none that fit into my my particular case scenario.</p> <p>I have a Windows Form with a Button. The button is attached to the event handler as follows:</p> <pre><code>private void mybutton_Click(object sender, EventArgs e) { // do some processing here } </code></pre> <p>In addition there is a combobox where a change in selection in supposed to trigger the button event handler as defined above.</p> <pre><code>private void mycombobox_SelectedIndexChanged(object sender, EventArgs e) { mybutton_Click(sender, e); // this is the line which pops up the dialog } </code></pre> <p>The code works exactly as intended at runtime but i get a dialog prompt at compile time which reads:</p> <blockquote> <p>object reference not set to an instance of an object</p> </blockquote> <p>There are no other errors or warning. </p> <p>A google search tells me that this message is an error caused if the program is trying to access a member of a reference type variable which is set to null.</p> <p>However when i run this code in debug mode, both the sender and event(e) variables are not null.</p> <p>So why is this dialog popping up ? </p> <p>And if this had been an error or warning - it should have shown as an error or warning but nothing of that sort happens. </p> <p>Here's the screenshot: <img src="https://i.stack.imgur.com/bfPwt.png" alt="enter image description here"></p> <p><strong>Edits: Answering Questions Raised in Comments</strong></p> <p>There are no errors as you can see in the screenshot.</p> <p>The program works great - just this pop up</p> <p>The popup is caused by the line:<code>mybutton_Click(sender, e);</code> in the combobox <code>selectedIndexChanged</code> function.</p> <p>The <code>mybutton_Click(sender, e)</code> does not use any of the arguments sender or e in the processing.</p> <p>I have not installed any VS extensions either.</p>
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    1. USMisha Zaslavsky
    1. USbhaskarc
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    1. COWhat code do you have in place of 'do some processing here'?
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    2. COwhat is location of hat error ? If it runs on RELEASE but produces problems *at compilation* in DEBUG, this could be related some Forms designer problem, usually restring VS resolves problem.
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      1. USTigran
    3. COyou say it happens at compile time? That makes no sense. post your stack trace!
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      1. USAhmed ilyas
 

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