取当月第几周：WEEKNUM(A2,2)-WEEKNUM(EOMONTH(A2,-1)+1,2)+1
取当年第几周：WEEKNUM(A2,2) 2表示从周一到周天算一周，1表示从周天到周六算一周。
转载于:https://www.cnblogs.com/starting/p/4487562.html
