c#计算时间差

/// <summary>
    /// 计算两个日期的时间间隔
    /// </summary>
    /// <param name="DateTime1">第一个日期和时间</param>
    /// <param name="DateTime2">第二个日期和时间</param>
    /// <returns></returns>
    public static string DateDiff(DateTime DateTime1, DateTime DateTime2)
    {
        string dateDiff = null;
        TimeSpan ts1 = new TimeSpan(DateTime1.Ticks);
        TimeSpan ts2 = new TimeSpan(DateTime2.Ticks);
        TimeSpan ts = ts1.Subtract(ts2).Duration();
        string days = ts.Days.ToString();
        string hours = ts.Hours.ToString();
        string minutes = ts.Minutes.ToString();
        string seconds = ts.Seconds.ToString();

        if (days != "0")
        {
            dateDiff += "" + ts.Days.ToString() + "天";
        }
        if (hours != "0")
        {
            dateDiff += "" + ts.Hours.ToString() + "小时";
        }
        if (minutes != "0")
        {
            dateDiff += "" + ts.Minutes.ToString() + "分钟";
        }
        if (seconds != "0")
        {
            dateDiff += "" + ts.Seconds.ToString() + "秒";
        }

        //dateDiff = ts.Days.ToString() + "天"
        //+ ts.Hours.ToString() + "小时"
        //+ ts.Minutes.ToString() + "分钟"
        //+ ts.Seconds.ToString() + "秒";

        return dateDiff;
    }