var tmp = new SumpleClass() ; var attrs = tmp.GetType().GetField( "Field" ).GetCustomAttributes( false ) ;
for (int i = 0; i < attrs.GetLength(0); ++i) { var myattr = attrs[i] as MyAttribute ; if (myattr == null) continue; System.Console.WriteLine("{0}", myattr.IntData); System.Console.WriteLine("{0}", tmp.Field); tmp.GetType().GetField("Field").SetValue(tmp, 100); System.Console.WriteLine("{0}", tmp.Field);