高手请指导：怎么求出给定日期所在的周数啊！

Question

using System.Globalization;GregorianCalendar gc = new GregorianCalendar();
Console.WriteLine(gc.GetWeekOfYear(DateTime.Now,CalendarWeekRule.FirstDay, DayOfWeek.Monday));

Answer 1

<script>
var dt = new Date()
var y= dt.getYear()
var start = "1/1/"+ y
start = new Date(start)
starts = start.valueOf()
startweek = start.getDay()
dtweek = dt.getDay()
var days = Math.round((dt.valueOf()- start.valueOf())/(24*60*60*1000))-(7-startweek) - dt.getDay()-1
days = Math.floor(days/7)
alert(days+2)
</script>
周日做为下周的开始计算

Answer 2

谢谢saucer(思归, MS .NET MVP) ，我试一试！！

Answer 3

var dt = new Date()
var y= dt.getYear()
var start = "1/1/"+ y
start = new Date(start)
starts = start.valueOf()
startweek = start.getDay()
dtweek = dt.getDay()
var days = Math.round((dt.valueOf()- start.valueOf())/(24*60*60*1000))-(7-startweek) - dt.getDay()-1
days = Math.floor(days/7)
alert(days+2)

Answer 4

<summary>
/// 获得第几周
/// </summary>
/// <param name="Day"></param>
/// <returns></returns>
private static int getWeekNum(DateTime Day)
{
int li_weeknum = 0;
GregorianCalendar gc = new GregorianCalendar();
DateTime l_monthfirst = gc.ToDateTime(gc.GetYear(Day),gc.GetMonth(Day),1,0,0,0,0);
string as_monthfirstweekday = Convert.ToString(gc.GetDayOfWeek(l_monthfirst));