Determine the name of a constant based on the value

Question

Is there a way of determining the name of a constant from a given value?

For example, given the following:

public const uint ERR_OK = 0x00000000;

Ho

Answer 1

In general, you can't. There could be any number of constants with the same value. If you know the class which declared the constant, you could look for all public static fields and see if there are any with the value 0, but that's all. Then again, that might be good enough for you - is it? If so...

public string FindConstantName(Type containingType, T value)
{
    EqualityComparer comparer = EqualityComparer.Default;

    foreach (FieldInfo field in containingType.GetFields
             (BindingFlags.Static | BindingFlags.Public))
    {
        if (field.FieldType == typeof(T) &&
            comparer.Equals(value, (T) field.GetValue(null)))
        {
            return field.Name; // There could be others, of course...
        }
    }
    return null; // Or throw an exception
}