C# 中传参中的OUT 和 ref 区别 笔记

//out传参前需要对参数进行赋值处理，ref则不需要。
//out、ref 传参都可以对值进行改变
 1 static void Main(string[] args)
 2         {
 3             int I = 10;
 4             //int J = 10;
 5             //int I;
 6             int J;
 7             //int[] k=new int[5]{1,2,3,4,5};
 8             int[] k = new int[5];
 9             //int[] l = new int[5]{1,2,3,4,5};
10             int[] l = new int[5];
11 
12             TestClass1 tc = new TestClass1();
13             tc.testClass(ref I);
14             tc.testClass1(out J);
15             
16             tc.testClass2(out k);
17             tc.testClass3(ref l);
18 
19             Console.WriteLine("out I:"+I);
20             Console.WriteLine("ref J:" + J);
21 
22             Console.WriteLine("out k[0]:" + k[0]);
23             Console.WriteLine("ref l[0]:" + l[0]);
24             Console.Read();
25         }
26         public  void testClass(ref int i)
27         {
28             i = 100;
29         }
30         public void testClass1(out int i)
31         {
32             i = 100;
33         }
34         public void testClass2(out int[] k)
35         {
36             k=new int[5];
37             k[0] = 100;
38         }
39         public void testClass3(ref int[] l)
40         {
41             l = new int[5];
42             l[0] = 100;
43         }
44 
45 
46     }