C# Error CS0631 – ref and out are not valid in this context

C# Error

CS0631 – ref and out are not valid in this context

Reason for the Error & Solution

ref and out are not valid in this context

The declaration for an cannot include the use of or parameters.

Example

The following sample generates CS0631:

// CS0631.cs  
public class MyClass  
{  
    public int this[ref int i]   // CS0631  
    // try the following line instead  
    // public int this[int i]  
    {  
        get  
        {  
            return 0;  
        }  
    }  
}  
  
public class MyClass2  
{  
    public static void Main()  
    {  
    }  
}