using System; public class My { bool ContentTransferEncoding { set { } } } public static class Test { public static int Main () { var test = new My (); int result = test.ContentTransferEncoding (); if (result != 1) return 1; result = test.ContentTransferEncoding (); if (result != 2) return 2; return 0; } public static int ContentTransferEncoding (this My email) { return 2; } public static int ContentTransferEncoding (this My email) { return 1; } }