HQ-day7 随机数案例：随机出验证码，对照输入，判断是否正确 

 1 string s = "abcdefghiklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890";
 2             for (; ; )
 3             {
 4                 Random ran = new Random();
 5                 int a = ran.Next(s.Length);   //随机抽取s内的字符a,b,c,d
 6                 int b = ran.Next(s.Length);
 7                 int c = ran.Next(s.Length);
 8                 int d = ran.Next(s.Length);
 9 
10                 string a1 = s.Substring(a, 1);//接收a,b,c,d的字符串a1,b1,c1,d1
11                 string b1 = s.Substring(b, 1);
12                 string c1 = s.Substring(c, 1);
13                 string d1 = s.Substring(d, 1);
14                 string ss = a1 + b1 + c1 + d1;//组成验证码
15                 Console.WriteLine(ss); //输出验证码
16 
17                 Console.Write("请输入验证码：");//用户输入验证码
18                 string yzm = Console.ReadLine();
19 
20                 string ss1 = ss.ToUpper();  //将输入的验证码全部转化为大写字符（或者小写）
21                 string yzm1 = yzm.ToUpper();
22 
23                 if (ss1 == yzm1)   //比对输入和显示是否一致
24                 {
25                     Console.WriteLine("输入正确");
26                     break;
27 
28                 }
29                 else
30                 {
31                     Console.WriteLine("您输入的有误！");
32                 }
33             }
34             Console.ReadLine();

 简化代码：

 1   string s = "abcdefghiklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890";
 2              for (; ; )
 3                 {
 4                     Random ran = new Random();
 5                
 6                     string biao = "";
 7                     for (int i = 1; i <= 4; i++)
 8                     {
 9                         biao += s.Substring(ran.Next(s.Length), 1);
10                     }
11                     Console.WriteLine(biao);
12                     Console.Write("请输入验证码");
13                     string shu = Console.ReadLine();
14                     if (shu.ToUpper() == biao.ToUpper())
15                     {
16                         Console.WriteLine("输入正确");
17                         break;
18 
19                     }
20 
21                     else
22                     {
23                         Console.Clear();
24                         Console.WriteLine("输入错误");
25                         
26                     }
27 
28                 }

 

posted @ 2016-03-12 10:15  天照丶鼬  阅读(311)  评论(0)    收藏  举报