统计某个字符串中指定字符串出现的次数

static void CountChar()

        {

            Console.WriteLine("请输入一个字符串：");

            string s = Console.ReadLine();

            Console.WriteLine("请输入要查询的子字符串：");

string[] sub ={Console.ReadLine()};

            string[] arr = s.Split(sub,StringSplitOptions.None);

            Console.WriteLine("{0}出现的次数为：{1}",sub[0],arr.Length-1);

        }