Question

我正在开发一个ASPX VB.NET文件。我的任务是将表示一年中一周的整数转换为该结束日期。例如，如果用户选择2011年的第4周，我想获得日期= 1/22/11。我如何在VB.NET中执行此操作？

Answer 1

不久前我问过a similar question。我还有an answer from J.Skeet的RegularExpressionValidator（如果你需要的话）。

以下是我必须从一周中的某一周获得的日期：

Public Shared Function FirstDateOfWeek(ByVal year As Integer, ByVal weekOfYear As Integer) As DateTime
      Dim jan1 As New DateTime(year, 1, 1)
      Dim daysOffset As Integer = CInt(Globalization.CultureInfo.CurrentCulture.DateTimeFormat.FirstDayOfWeek) - CInt(jan1.DayOfWeek)
      Dim firstWeekDay As DateTime = jan1.AddDays(daysOffset)
      Dim curCulture As System.Globalization.CultureInfo = System.Globalization.CultureInfo.CurrentCulture
      Dim firstWeek As Integer = curCulture.Calendar.GetWeekOfYear(jan1, curCulture.DateTimeFormat.CalendarWeekRule, curCulture.DateTimeFormat.FirstDayOfWeek)
      If firstWeek <= 1 Then
          weekOfYear -= 1
      End If
      Return firstWeekDay.AddDays(weekOfYear * 7)
End Function

这里是RegularExpressionValidator，虽然我的格式（07w42表示2007年的42.week）与你的格式略有不同。

<asp:RegularExpressionValidator ID="CalWeekFormat" runat="server" 
                                 ControlToValidate="TxtCalWeek" Display="None" EnableClientScript="true" 
                                 ErrorMessage="Enter valid Year/Calendarweek-Format: examplary format '09w23' or '9w23' for year 2009 and week 23" 
                                 style="visibility:hidden" 
                                 ValidationExpression="^\d{1,4}[wW](\d|[0-4]\d|5[0123])$" 
                                 ValidationGroup="VG_SAVE">*</asp:RegularExpressionValidator>

Answer 2

您可以使用Time Period Library for .NET的周：

Imports Itenso.TimePeriod

Module GetStartOfWeekDemo

    Sub Main()

        Console.WriteLine("Week start " & GetStartOfWeek(2011, 4))
        Console.ReadKey()

    End Sub

    Public Function GetStartOfWeek(ByVal year As Integer, ByVal weekOfYear As Integer) As DateTime

        Dim week As Week = New Week(year, weekOfYear)
        Return week.Start

    End Function

End Module

vb.net周转换？

2 个答案: