Compiler Error CS0136

A local variable named 'var' cannot be declared in this scope because it would give a different meaning to 'var', which is already used in a 'parent or current/child' scope to denote something else

A variable declaration hides another declaration that would otherwise be in scope. Rename the variable that is declared on the line that generated CS0136.

Example

The following sample generates CS0136:

// CS0136.cs  
namespace MyNamespace  
{  
   public class MyClass  
   {  
      public static void Main()  
      {  
         int i = 0;  
         {  
            char i = 'a';   // CS0136, hides int i  
         }  
         i++;  
      }  
   }  
}  

From the C# Language Specification:

It is an error for a local variable declaration space and a nested local variable declaration space to contain elements with the same name. Thus, within a nested declaration space it is not possible to declare a local variable or constant with the same name as a local variable or constant in an enclosing declaration space. It is possible for two declaration spaces to contain elements with the same name as long as neither declaration space contains the other.