Question

我想将日期添加到给定开始日期和结束日期的数组中。

我已经尝试过将其声明为Array和ArrayList，但是在同一行给出了相同的错误。这是示例代码：

Dim startP As DateTime = New DateTime(2019, 3, 27)
Dim endP As DateTime = New DateTime(2019, 3, 30)
Dim CurrD As DateTime = startP
Dim DateArray As ArrayList

Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
    While (CurrD <= endP)
        DateArray.Add(CurrD)
        CurrD = CurrD.AddDays(1)
    End While
End Sub

两个都给出了错误“未处理NullReferenceException”

Answer 1

由于未初始化DateArray.，您会遇到错误：

Dim DateArray As New ArrayList

Answer 2

列表可能是一个更好的选择。请注意示例中的列表是如何初始化的。

Dim startP As DateTime = New DateTime(2019, 3, 27)
Dim endP As DateTime = New DateTime(2019, 3, 30)
Dim CurrD As DateTime = startP
Dim DateArray As New List(Of DateTime)

Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
    While (CurrD <= endP)
        DateArray.Add(CurrD)
        CurrD = CurrD.AddDays(1)
    End While
    'where you need an array of DateTime do
    '   DateArray.ToArray
End Sub

Answer 3

您可以执行以下操作。

  Dim date_array As New List(Of Date)
  date_array.Add(New Date()) ' add as much as you want in a loop or manually
  date_array.ToArray() ' to return an array of dates..

如何将日期添加到数组？

3 个答案: