using System; using System.Reflection; class A1 : Attribute { public float F; public float UL; public A1 (float f) { this.F = f; } public A1 (ulong ul) { this.UL = ul; } } [A1 (45234.567f)] class T1 { } [A1 (uint.MaxValue + (ulong)1)] class T2 { } class Test { public static int Main () { var A1 = typeof (T1).GetCustomAttributes (false) [0] as A1; if (A1.F != 45234.567f) return 1; A1 = typeof (T2).GetCustomAttributes (false) [0] as A1; if (A1.UL != uint.MaxValue + (ulong)1) return 2; return 0; } }