public string ConverNo(string str)

        {

            string result = "";

            char[] chars = new char[];

            for (int i = ; i < chars.Length; i++)

            chars[i] = '';

            char[] chars1 = str.ToArray(); //字符串生成数组

            string str0 = "";

            result =  str0.Substring(,str0.Length-str.Length);

            result = result += str;

            return "";

        }