获取某天为该年的第几周

    //今天为本年第几周
  //获取  
  CultureInfo   myCI   =   new   CultureInfo("zh-CN");  
  System.Globalization.Calendar   myCal   =   myCI.Calendar;  
   
  //日期格式  
  CalendarWeekRule   myCWR   =   myCI.DateTimeFormat.CalendarWeekRule;  
  DayOfWeek   myFirstDOW   =   DayOfWeek.Monday;  
  //本周为第myCal.GetWeekOfYear(   DateTime.Now,   myCWR,   myFirstDOW   )周  
  int   thisWeek=myCal.GetWeekOfYear(   DateTime.Now,   myCWR,   myFirstDOW   );