How to make array elements into a string in which each array element separated by comma(,) without using array properties or any predefined functions

 string[] names = new string[5] { "Matt", "Joanne", "Robert" ,"hello","howareu"};
        string str = string.Empty;
       int temp=0;
    try
       {
           while (names[temp+1] != null)
           {
             
               str += names[temp] + ",";
               temp++;
           }
       }
       catch(Exception ee)
       {
           str += names[temp];
       }
        Response.Write(str);