类的实例1

           Console.Write("请输入一个字符串：");
            string strA = Console.ReadLine();
            Console.Write("请输入要查找的字符串：");
            string strB = Console.ReadLine();
            strA = strA.ToLower();
            strB = strB.ToLower();
           // if (strA.Contains(strB))
            //{
                int n = 0;
            //int i=1
                //while (i != -1) 
                int i;
                do
                {
                    i = strA.IndexOf(strB);//找不到返回-1
                    strA = strA.Substring(i + 1);
                    n++;
                }
                while (i != -1);
                Console.Write("查找的字符串的个数为" + (n - 1).ToString());
           // }
            //else 
            //{
               // Console.Write("没有");
           // }

            Console.ReadLine();