带静态类的C＃NullReferenceException

Question

I have a static class:

namespace GVN  
{  
    static class ClData      
    {  
        public static string cltNM {get; set;}  
    }  
}    

But, when I try to use it,

label_nm.Text = ClData.cltNM;  

this error appears: ( http://msdn.microsoft.com/library/vstudio/sxw2ez55 )

Even if I perform this manually:

ClData.cltNM = "12345";    

Before:

label_nm.Text = ClData.cltNM;        

How can I avoid this error?

Answer 1

Your problem is that label_nm is null , rather than the static string variable, or the error is not in fact on the line of code that you've indicated. Even if cltNM is null it wouldn't throw a null reference exception on that line.