Compiler Error CS0031

Constant value 'value' cannot be converted to a 'type'.

An attempt was made to assign a value to a variable whose type cannot store the value. For more information, see Types.

The following sample generates CS0031 in both checked and unchecked contexts:

// CS0031.cs
namespace CS0031
{
    public class Program
    {
        public static void Main()
        {
            int num = (int)2147483648M; //CS0031
            // Try using a larger numeric type instead.
            // long num = (long)2147483648M; //CS0031

            const decimal d = -10M; // Decimal literal
            unchecked
            {
                const byte b = (byte)d; // CS0031
                // For small values try using a signed byte instead.
                // const sbyte b = (sbyte)d;
            }
        }
    }
}

See also

• unchecked