总结的5个C#字符串操作方法分享

/// <summary> 
    /// 把字符串按照分隔符转换成 list 
    /// </summary> 
    /// <param name="str">源字符串</param> 
    /// <param name="speater">分隔符</param> 
    /// <param name="tolower">是否转换为小写</param> 
    /// <returns></returns> 
    public static list<string> getstrarray(string str, char speater, bool tolower)
    {
      var list = new list<string>();
      var ss = str.split(speater);
      foreach (var s in ss)
      {
        if (string.isnullorwhitespace(s) || s == speater.tostring(cultureinfo.invariantculture)) continue;
        var strval = s;
        if (tolower)
        {
          strval = s.tolower();
        }
        list.add(strval);
      }
      return list;
    }

/// <summary> 
    /// 把字符串转 按照, 分割 换为数据 
    /// </summary> 
    /// <param name="str"></param> 
    /// <returns></returns> 
    public static string[] getstrarray(string str)
    {
      return str.split(new[] { ',', '，' });
    }

/// <summary>
    /// 得到数组列表以逗号分隔的字符串
    /// </summary>
    /// <param name="list"></param>
    /// <param name="speater"></param>
    /// <returns></returns>
    public static string getarraystr(list<string> list, string speater)
    {
      var sb = new stringbuilder();
      for (var i = 0; i < list.count; i++)
      {
        if (i == list.count - 1)
        {
          sb.append(list[i]);
        }
        else
        {
          sb.append(list[i]);
          sb.append(speater);
        }
      }
      return sb.tostring();
    }

/// <summary>
    /// 得到字符串长度
    /// </summary>
    /// <param name="inputstr"></param>
    /// <returns></returns>
    public static int strlength(string inputstr)
    {
      var asc = new asciiencoding();
      var s = asc.getbytes(inputstr);
      return s.sum(t => t == 63 ? 2 : 1);
    }

/// <summary>
    /// 截取指定长度字符串
    /// </summary>
    /// <param name="inputstring"></param>
    /// <param name="len"></param>
    /// <returns></returns>
    public static string cutstr(string inputstring, int len)
    {
      var isshowfix = false;
      if (len % 2 == 1)
      {
        isshowfix = true;
        len--;
      }
      var ascii = new asciiencoding();
      var templen = 0;
      var tempstring = "";
      var s = ascii.getbytes(inputstring);
      for (var i = 0; i < s.length; i++)
      {
        templen += s[i] == 63 ? 2 : 1;
        try
        {
          tempstring += inputstring.substring(i, 1);
        }
        catch
        {
          break;
        }

        if (templen > len)
          break;
      }

      var mybyte = encoding.default.getbytes(inputstring);
      if (isshowfix && mybyte.length > len)
        tempstring += "…";
      return tempstring; 
    }