.NET 中 截取中英混字

        public  string CutString(string str, int length)
        {
            if (str == "")
            {
                str = "没有信息";
            }
            else
            {
                int i = 0, j = 0;
                foreach (char chr in str)
                {
                    if ((int)chr > 127)
                    {
                        i += 2;
                    }
                    else
                    {
                        i++;
                    }
                    if (i > length)
                    {
                        str = str.Substring(0, j);
                        break;
                    }
                    j++;
                }

            }
            return str;
        }