string s = "8,2,3,7,9," //处理后变成 “8,2,3,7,9”
string s = "8,2,3,7,9," s = s.Substring(0,s.Length - 1)
string s = "8,2,3,7,9," s=s.TrimEnd(',') //如果要删除"9,",则需要这么写 char[] MyChar = {'9',','}; s = s.TrimEnd(MyChar);
string s = "8,2,3,7,9," s = s.Remove(a.Length - 1,1); //移除掉","