C#——计算两个字符串日期的时间差或天数差

计算某年某月的天数

	DateTime dt1 = Convert.DateTime("2007-8-1"); 
	DateTime dt2 = Convert.DateTime("2007-8-15"); 
	TimeSpan span = dt2.Subtract(dt1); 
	int dayDiff = span.Days + 1; 

获取当前时间;

  DateTime checkTime =DateTime.Now

转自：
https://www.cnblogs.com/yechangzhong-826217795/p/5127489.html