本文給出一個方法（函數）用來獲得當前星期的周六和周日，這在我們日常編程中經常能使用到。

方法的名字為：ConvertDateToWeek

#region ConvertDateToWeek

public static void ConvertDateToWeek(DateTime date,out DateTime firstdate,out DateTime lastdate)
        {   
            DateTime first=System.DateTime.Now;
            DateTime last=System.DateTime.Now;
            switch (date.DayOfWeek)
            {               
                case System.DayOfWeek.Monday:
                    first=date.AddDays(-1);
                    last=date.AddDays(5);
                    break;
                case System.DayOfWeek.Tuesday:
                    first=date.AddDays(-2);
                    last=date.AddDays(4);
                    break;
                case System.DayOfWeek.Wednesday:
                    first=date.AddDays(-3);
                    last=date.AddDays(3);
                    break;
                case System.DayOfWeek.Thursday:
                    first=date.AddDays(-4);
                    last=date.AddDays(2);
                    break;
                case System.DayOfWeek.Friday:
                    first=date.AddDays(-5);
                    last=date.AddDays(1);
                    break;
                case System.DayOfWeek.Saturday:
                    first=date.AddDays(-6);
                    last=date;
                    break;
                case System.DayOfWeek.Sunday:
                    first=date;
                    last=date.AddDays(6);
                    break;               
            }
            firstdate=first;
            lastdate=last;
        }
        #endregion   

具體使用方法如下：

DateTime firstdate=System.DateTime.Now;   

DateTime lastdate=System.DateTime.Now;

ConvertDateToWeek(date,out firstdate,out lastdate);