在VB中将日、周数和年转换为日期

Question

我需要帮助来转换年份、周数和日期。因此，如果 date1 是 1990，wN 是 12，dDay 是 3，则结果应该是 3/21/1990（mm/dd/yyyy 格式）。

我在为这一行找到正确的格式时遇到问题：Output(Date(date1, 1, 1) + ((wN - 1) * 7) - Weekday(Date(date1, 1, 1) + (wN - 1) * 7, 2) + 1 + (dDay - 1))

此代码在 Excel 中运行良好。我正在尝试将其转换为在 vb.net 中工作

    Dim str1 As String = txtInput1.Text
    Dim d2 As String
    Dim date1 As Integer
    Dim date2 As Integer
    Dim wN As Integer
    Dim dDay As Integer

    Dim cYear As Integer = DateTime.Now.Year

    txtOutput.Text = ""

    d2 = Mid(str1, 2, 1)
    wN = Mid(str1, 3, 2)
    dDay = Mid(str1, 5, 1)

    If d2 = "G" Then
        date1 = 1990
        date2 = 2013
        If date2 <= cYear Then
            'Output("Year Built " & date1 & " or " & date2 & vbCrLf & "Week " & wN & vbCrLf & "Day " & dDay)
            Output(Date(date1, 1, 1) + ((wN - 1) * 7) - Weekday(Date(date1, 1, 1) + (wN - 1) * 7, 2) + 1 + (dDay - 1))
        Else
            Output("Year Built " & date1)
        End If

Answer 1

你的公式有点不对劲。从年初开始，加上天数。

    Const DAYS_IN_A_WEEK As Integer = 7

    Dim year As Integer = 1990
    Dim weekNumber As Integer = 12
    Dim dayOfWeek As Integer = 3

    Dim calculatedDate = New DateTime(year, 1, 1)
    calculatedDate = calculatedDate.AddDays((weekNumber - 1) * DAYS_IN_A_WEEK + (dayOfWeek - 1) - (CInt(calculatedDate.DayOfWeek) - 1))