System.RuntimeFieldHandle.IsNullHandle C# (CSharp) Method

        internal bool IsNullHandle() 
        { 
            return m_ptr.ToPointer() == null; 
        }

        public static FieldInfo GetFieldFromHandle(RuntimeFieldHandle handle, RuntimeTypeHandle declaringType)
        {
            if (handle.IsNullHandle())
                throw new ArgumentException(Environment.GetResourceString("Argument_InvalidHandle"));

            return RuntimeType.GetFieldInfo(declaringType.GetRuntimeType(), handle.GetRuntimeFieldInfo());
        }