Question

我有这个结构：

Public strcMyInfo As DISPLAYDIRECTORY
Public arrDirectory As ArrayList

Public Structure DISPLAYDIRECTORY
    Dim strdirno As String
    Dim strdirname As String
    Dim strdirdetails As String
    Dim strcategory As String
    Dim strwebsite As String
    Dim strphoneno As String
End Structure

我将对数据库进行查询，并将结构strcMyInfo添加到arrDirectory。 arrDirectory将保存包含strcMyInfo数据的数据，即10个索引。例如，arrDirectory.Item(6).strdirname的值是G2000。如何循环遍历arraylist以找到G2000的值以及strdirno, strdirdetails,strcategory,strwebsite and strphoneno？

我已经搜索了互联网，但在添加以下示例时，他们只查找1值：

myAL.Add("the")
myAL.Add("quick")
myAL.Add("brown")
myAL.Add("fox")
myAL.Add("jumps")
myAL.Add("over")
myAL.Add("the")
myAL.Add("lazy")
myAL.Add("dog")

但我的代码将是这样的：

If (rdr.HasRows()) Then
     arrDirectory = Nothing
     arrDirectory = New ArrayList
     While rdr.Read
          With strcSearchDir
                  If Not IsDBNull("dirno") Then
                            .strdirno = (rdr("dirno"))
                  Else
                            .strdirno = "N/A"
                  End If
                  If Not IsDBNull("dirname") Then
                            .strdirname = (rdr("dirname"))
                  Else
                            .strdirname = "N/A"
                  End If
                  If Not IsDBNull("dirdetails") Then
                            .strdirdetails = (rdr("dirdetails"))
                  Else
                            .strdirdetails = "N/A"
                  End If
                  If Not IsDBNull("category") Then
                            .strcategory = (rdr("category"))
                  Else
                            .strcategory = "N/A"
                  End If
                  If Not IsDBNull("website") Then
                            .strwebsite = (rdr("website"))
                  Else
                            .strwebsite = "N/A"
                  End If
                  If Not IsDBNull("phoneno") Then
                            .strphoneno = (rdr("phoneno"))
                  Else
                            .strphoneno = "N/A"
                  End If
          End With
          arrDirectory.Add(strcSearchDir)
     End While
     Return True
Else
     Return False
End If

下面是找到字符串的代码，但它停在那里因为我不知道如何继续：

Private Sub GetMyDetails(ByVal strLabel As Label)
        Dim obj As Object
        Try
            If strLabel.Content <> String.Empty Then
                For Each obj In arrDirectory
                    If arrDirectory.IndexOf(obj) = strLabel.Content Then

                    End If
                Next
            End If
        Catch ex As Exception

        End Try
End Sub

如果有人知道如何在arraylist中使用indexof，请指导我。谢谢

Answer 1

您根本不应该使用IndexOf。 For Each循环的重点是访问项目本身，然后您希望获取具有特定字段/属性的特定值的项目。

Private Function GetMyDetails(ByVal strDirName As String) As DISPLAYDIRECTORY
    Dim obj As DISPLAYDIRECTORY

    Try
        If strDirName <> String.Empty Then
            For Each item As DISPLAYDIRECTORY In arrDirectory
                If item.strdirname = strDirName Then
                    obj = item
                    Exit For
                End If
            Next
        End If
    Catch ex As Exception

    End Try

    Return obj
End Sub

VB.NET在arraylist中查找值

1 个答案: