mcs/tests/dtest-null-operator-01.cs

   1 using System;
   2 using System.Collections.Generic;
   3 using System.Linq;
   4
   5 class X
   6 {
   7         public string Prop;
   8         public A A = new A ();
   9 }
  10
  11 class A
  12 {
  13         public string B;
  14 }
  15
  16 class MainClass
  17 {
  18         static void NullCheckTest ()
  19         {
  20                 dynamic dyn = null;
  21                 dynamic res;
  22
  23                 res = dyn?.ToString ();
  24                 res = dyn?.GetHashCode ();
  25                 res = dyn?.DD.Length?.GetHashCode ();
  26
  27                 dyn?.ToString ();
  28
  29                 res = dyn?.Prop;
  30                 res = dyn?.Prop?.Prop2;
  31                 res = dyn?[0];
  32         }
  33
  34         static void Test_1 ()
  35         {
  36                 dynamic dyn = new X ();
  37                 dynamic res;
  38
  39                 res = dyn.Prop?.Length;
  40                 res = dyn.A.B?.C.D?.E.F;
  41         }
  42
  43         static dynamic Test_2 (IEnumerable<dynamic> collection)
  44         {
  45                 return collection?.FirstOrDefault ().Length;
  46         }
  47
  48         public static void Main ()
  49         {
  50                 NullCheckTest ();
  51
  52                 Test_1 ();
  53                 Test_2 (null);
  54         }
  55 }
  56
  57