Question

这是一个简单的代码但是真的洗了我的大脑..移动到任何位置代码都无济于事。下面是在从combobox添加新项目之前检查listview中的每个项目。不幸的是只检查最后一项的工作。帮我。提前致谢

Dim checkType As String
        Dim checkSubType As String
        Dim TempNode As ListViewItem
        For Each TempNode In ListView1.Items
            checkSubType = TempNode.SubItems.Item(0).Text
            checkType = TempNode.SubItems.Item(1).Text
        Next

        If ComboBox1.Text = checkSubType AndAlso ComboBox2.Text = checkType Then
            With ListView1.Items.Add(ComboBox1.Text, 0)
                .SubItems.Add(ComboBox2.Text)
                .SubItems.Add("DUPLICATE")
            End With
        Else
            With ListView1.Items.Add(ComboBox1.Text, 0)
                .SubItems.Add(ComboBox2.Text)
                .SubItems.Add("ADD NEW")
            End With
        End If

解决方案：

 Dim total As Integer
        If ListView1.View = View.Details AndAlso ListView1.Items.Count > 0 Then
            'Dim lvi As ListViewItem = ListView1.FindItemWithText(ComboBox1.Text, True, 0)
            Dim lva As ListViewItem = ListView1.FindItemWithText(ComboBox2.Text, True, 0)

            If lva IsNot Nothing Then
                '......
            Else
                '......
            End If
        Else
            '......
        End If

Answer 1

问题出在For Each循环中。每次循环时，都会消除checkSubType和checkType中的旧值并在其上保存新值。这就是为什么只检查最后一项。

Dim checkType as List(Of String) = new List(Of String)
Dim checkSubType as List(Of String) = new List(Of String)


For Each TempNode In ListView1.Items
        checkSubType.Add(TempNode.SubItems.Item(0).Text)
        checkType.Add(TempNode.SubItems.Item(1).Text)
Next

此时，您现在有两个完整的项目列表，然后可以检查它们。

或者你可以试试这样的东西

Dim checkType As String
    Dim checkSubType As String
    Dim TempNode As ListViewItem

    For value As Integer 0 To ListView1.Items.Count
        checkSubType = TempNode.SubItems.Item(0).Text
        checkType = TempNode.SubItems.Item(1).Text


    If ComboBox1.Text = checkSubType AndAlso ComboBox2.Text = checkType Then
        With ListView1.Items.Add(ComboBox1.Text, 0)
            .SubItems.Add(ComboBox2.Text)
            .SubItems.Add("DUPLICATE")
        End With
    Else
        With ListView1.Items.Add(ComboBox1.Text, 0)
            .SubItems.Add(ComboBox2.Text)
            .SubItems.Add("ADD NEW")
        End With
    End If
Next

如何检查每个项目列表视图

1 个答案: