c# 标点问题

Question

%4==0   
+","
TrimEnd(',')

Answer 1

string strNum="90099030906290631";
            string res ="";
            int i = 0;
            while (i+4 < strNum.Length)
            {
                res += strNum.Substring(i, 4) + ",";
                i = i + 4;
            }

Answer 2

string text = @"9009903090629063";
            List<string> list = Regex.Split(text,@"(?<=\G\w{4})(?!$)").ToList();
            /*
             *  [0] "9009" string
            [1] "9030" string
            [2] "9062" string
            [3] "9063" string             */

Answer 3

string text = @"9009903090629063";
string newtext = "'"+text.Substring(0, 4) + "','" + text.Substring(4, 4) + "','" + text.Substring(8, 4) + "','" + text.Substring(12, 4)+"'";
        

Answer 4

帅哥啊，Session["ESI_EMPNO"]=“‘9009’，‘9030’，‘9062’，‘9063’”这个结果怎么得到

Answer 5

帅哥啊，Session["ESI_EMPNO"]=“‘9009’，‘9030’，‘9062’，‘9063’”这个结果怎么得到=。= list[0] == '9009',list[1],list[2],list[3]……

Answer 6

string text = @"9009903090629063";
            string s=string.Join( ",",Regex.Split(text,@"(?<=\G\w{4})(?!$)").Select(a=>string.Format("'{0}'",a)));
            //"'9009','9030','9062','9063'"