Compiler Error CS0220

The operation overflows at compile time in checked mode

An operation was detected by checked, which is the default for constant expressions, and a data loss resulted. Either correct the inputs to the assignment or use unchecked to resolve this error. For more information, see the checked and unchecked statements article.

The following sample generates CS0220:

// CS0220.cs  
using System;  
  
class TestClass  
{  
   const int x = 1000000;  
   const int y = 1000000;  
  
   public int MethodCh()  
   {  
      int z = (x * y);   // CS0220  
      return z;  
   }  
  
   public int MethodUnCh()  
   {  
      unchecked  
      {  
         int z = (x * y);  
         return z;  
      }  
   }  
  
   public static void Main()  
   {  
      TestClass myObject = new TestClass();  
      Console.WriteLine("Checked  : {0}", myObject.MethodCh());  
      Console.WriteLine("Unchecked: {0}", myObject.MethodUnCh());  
   }  
}