Compiler Warning (level 2) CS0464

Comparing with null of type 'type' always produces 'false'

This warning is produced when you perform a comparison between a nullable value type variable and null, and the comparison is not == or !=. To resolve this error, verify if you really want to check a value for null. A comparison like i == null can be either true of false. A comparison like i > null is always false.

Example

The following sample generates CS0464.

// CS0464.cs  
class MyClass  
{  
   public static void Main()  
   {  
      int? i = 0;  
      if (i < null) ;   // CS0464  
  
      i++;  
   }  
}