.NET截取指定长度汉字超出部分以"..."代替 实例分享

///   <summary>
    ///   将指定字符串按指定长度进行剪切，
    ///   </summary>
    ///   <param   name= "oldstr "> 需要截断的字符串 </param>
    ///   <param   name= "maxlength "> 字符串的最大长度 </param>
    ///   <param   name= "endwith "> 超过长度的后缀 </param>
    ///   <returns> 如果超过长度，返回截断后的新字符串加上后缀，否则，返回原字符串 </returns>
    public static string stringtruncat(string oldstr, int maxlength, string endwith)
    {
        if (string.isnullorempty(oldstr))
            //   throw   new   nullreferenceexception( "原字符串不能为空 ");
            return oldstr + endwith;
        if (maxlength < 1)
            throw new exception("返回的字符串长度必须大于[0] ");
        if (oldstr.length > maxlength)
        {
            string strtmp = oldstr.substring(0, maxlength);
            if (string.isnullorempty(endwith))
                return strtmp;
            else
                return strtmp + endwith;
        }
        return oldstr;
    }