I HAVE THIS ERROR object reference not set to an instance of an object.

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HERES MY CODE WHATS WRONG WITH THAT

 Private Sub ComboBox2_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ComboBox2.SelectedIndexChanged


        Dim intSelectedIndex As Integer
        intSelectedIndex = ComboBox2.SelectedIndex
        Dim objSelectedItem As Object
        objSelectedItem = ComboBox2.SelectedValue

        TextBox6.Text = objSelectedItem.ToString()

    End Sub
End Class

What I have tried:

I HAVE THIS ERROR Object reference not set to an instance of an object.

Posted 13-Feb-18 1:01am

Shaddow>dark

Updated 13-Feb-18 1:46am

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CHill60 13-Feb-18 7:04am

It looks like ComboBox2 does not have a selected value, so objSelectedItem is a null object.

Shaddow>dark 13-Feb-18 7:21am

thank you mr CHilll your good man <3

F-ES Sitecore 13-Feb-18 7:12am

This question is asked every day, please do basic research like using google before asking a question.

Shaddow>dark 13-Feb-18 7:20am

am i noising you ?? :)
i'm here for guys like you help us i mean fresh people in codes and you are here to help i think but thank you for your replay it was pleasure to Talk to you mr F :)

F-ES Sitecore 13-Feb-18 7:23am

It's basic etiquette to search before asking a question regardless of the forum you are using. If you'd searched for this error you will see the advice is always the same, it never changes.

Shaddow>dark 13-Feb-18 7:26am

some codes in google doesn't describe my problem its just give a ready code i need to learn from my errors mR F that's it :)

F-ES Sitecore 13-Feb-18 7:35am

Obviously you're not going to find a solution that has your exact code however you'll find plenty revolving around combo boxes.. However the advice on what to do to handle the error and look for the causes remains the same.

What you need to learn is how to use the debugger to step through your code, and what relevant information you need to supply to ask a good question that people can actually answer.

Dave Kreskowiak 13-Feb-18 8:59am

Stop using code you get from Google and start using the debugger.

Your question and the code you posted says that you don't know about or use the debugger. That's a HUGE problem for you. It's not there to tell you what's wrong with your code. It's there to debug YOU and your understanding of the code and how it executes. It's a tool to inspect the code as it's running, showing you that your understanding of the code is very different from reality.

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OriginalGriff · Answer 1 · 2018-02-13T01:46:00

This is one of the most common problems we get asked, and it's also the one we are least equipped to answer, but you are most equipped to answer yourself.

Let me just explain what the error means: You have tried to use a variable, property, or a method return value but it contains null - which means that there is no instance of a class in the variable.
It's a bit like a pocket: you have a pocket in your shirt, which you use to hold a pen. If you reach into the pocket and find there isn't a pen there, you can't sign your name on a piece of paper - and you will get very funny looks if you try! The empty pocket is giving you a null value (no pen here!) so you can't do anything that you would normally do once you retrieved your pen. Why is it empty? That's the question - it may be that you forgot to pick up your pen when you left the house this morning, or possibly you left the pen in the pocket of yesterdays shirt when you took it off last night.

We can't tell, because we weren't there, and even more importantly, we can't even see your shirt, much less what is in the pocket!

Back to computers, and you have done the same thing, somehow - and we can't see your code, much less run it and find out what contains null when it shouldn't.
But you can - and Visual Studio will help you here. Run your program in the debugger and when it fails, VS will show you the line it found the problem on. You can then start looking at the various parts of it to see what value is null and start looking back through your code to find out why. So put a breakpoint at the beginning of the method containing the error line, and run your program from the start again. This time, VS will stop before the error, and let you examine what is going on by stepping through the code looking at your values.

But we can't do that - we don't have your code, we don't know how to use it if we did have it, we don't have your data. So try it - and see how much information you can find out!