问个时间计算问题 急急急

[AA123456]

请问,如何根据当前日期,计算出1.当前日期前一周 周四是几号 2,当前日期本周 周五是几号
当前日期就是DateTime.Now

[ljhcy99]

1。

DateTime date = DateTime.Now;
DateTime date2 = date.AddDays(-7);
DayOfWeek t = date2.DayOfWeek;


2。DayOfWeek t1 =DateTime.Now.DayOfWeek;

[chinaicm]

DateTime dt1 = DateTime.Now.AddDays(DayOfWeek.Thursday - DateTime.Now.DayOfWeek-7);            

第一题

DateTime dt2 = DateTime.Now.AddDays(DayOfWeek.Friday - DateTime.Now.DayOfWeek);

第二题

[尐孑]

[Quote=引用 2 楼 chinaicm 的回复:]
C# code
DateTime dt1 = DateTime.Now.AddDays(DayOfWeek.Thursday - DateTime.Now.DayOfWeek-7);


第一题


C# code
DateTime dt2 = DateTime.Now.AddDays(DayOfWeek.Friday - DateTime.Now.DayOfWeek);


第二题
[/Quote].

[ljhcy99]

修改了
1,
DateTime date = DateTime.Now.AddDays(-7);
DayOfWeek t = date.DayOfWeek;
DateTime Date2 = DateTime.MinValue;
if (t != DayOfWeek.Friday)
{
switch (t)
{
case DayOfWeek.Monday:
Date2 = date.AddDays(4);
break;
case DayOfWeek.Saturday:
Date2 = date.AddDays(-1);
break;
case DayOfWeek.Sunday :
Date2 = date.AddDays(-2);
break;
case DayOfWeek.Thursday:
Date2 = date.AddDays(1);
break;
case DayOfWeek.Tuesday:
Date2 = date.AddDays(3);
break;
case DayOfWeek.Wednesday:
Date2 = date.AddDays(2);
break;
}
if (Date2 != DateTime.MinValue)
{
int tt2 = Date2.Day;
}
}


2，

DateTime date = DateTime.Now;
DayOfWeek t = date.DayOfWeek;
DateTime Date2 = DateTime.MinValue;
if (t != DayOfWeek.Friday)
{
switch (t)
{
case DayOfWeek.Monday:
Date2 = date.AddDays(4);
break;
case DayOfWeek.Saturday:
Date2 = date.AddDays(-1);
break;
case DayOfWeek.Sunday :
Date2 = date.AddDays(-2);
break;
case DayOfWeek.Thursday:
Date2 = date.AddDays(1);
break;
case DayOfWeek.Tuesday:
Date2 = date.AddDays(3);
break;
case DayOfWeek.Wednesday:
Date2 = date.AddDays(2);
break;
}
if (Date2 != DateTime.MinValue)
{
int tt2 = Date2.Day;
}
}

[大头_衍]

2楼的方便简洁

[cmaisyd]

        protected void Page_Load(object sender, EventArgs e)
        {
            DateTime DateNow = DateTime.Now;
            int Days = DayOfWeek.Thursday - DateTime.Now.DayOfWeek;
            DateTime LastThursday = DateNow.AddDays(Days - 7);
            Response.Write("<br/>上星期 星期四是：" + LastThursday.ToShortDateString());
            Days = DayOfWeek.Friday - DateTime.Now.DayOfWeek;
            DateTime ThisFriday = DateNow.AddDays(Days);
            Response.Write("<br/>这星 星期五是：" + ThisFriday.ToShortDateString());
        }

[renhua19831012]

DateTime datenow = DateTime.Now;//当前时间
int days = DayOfWeek.Thursday - DateTime.Now.DayOfWeek;
//当前和星期四时间之差(比如今天是星期三,那么时间之差就是1)
DateTime lastThur = datenow.AddDays(days - 7);//上个星期四的日期

System.Console.Write("上星期 星期四是：" + lastThur.ToShortDateString());
days = DayOfWeek.Friday - DateTime.Now.DayOfWeek;
////当前和星期五时间之差(比如今天是星期三,那么时间之差就是2)
DateTime thisfriday = datenow.AddDays(days);//这个星期五的日期
System.Console.Write("这个星期 星期五是：" + thisfriday.ToShortDateString());