1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
|
//-- ex-nullable-bool
using System;
class MyTest {
public static void Main(String[] args) {
Console.WriteLine("Note that null prints as blank or []\n");
bool? b1 = null, b2 = false, b3 = true;
bool? b4 = b1^b2, b5 = b1&b2, b6 = b1|b2; // null false null
Console.WriteLine("[{0}] [{1}] [{2}]", b4, b5, b6);
bool? b7 = b1^b3, b8 = b1&b3, b9 = b1|b3; // null null true
Console.WriteLine("[{0}] [{1}] [{2}]", b7, b8, b9);
Console.WriteLine(b1 != null ? "null is true" : "null is false"); // null is false
Console.WriteLine(b1 == null ? "!null is true" : "!null is false"); // !null is false
Console.WriteLine();
bool?[] bvals = new bool?[] { null, false, true };
Console.WriteLine("{0,-6} {1,-6} {2,-6} {3,-6} {4,-6}",
"x", "y", "x&y", "x|y", "x^y");
foreach (bool? x in bvals)
foreach (bool? y in bvals)
Console.WriteLine("{0,-6} {1,-6} {2,-6} {3,-6} {4,-6}",
x, y, x&y, x|y, x^y);
Console.WriteLine();
Console.WriteLine("{0,-6} {1,-6}", "x", "!x");
foreach (bool? x in bvals)
Console.WriteLine("{0,-6} {1,-6}", x, !x);
}
}
|
