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我有一个使用具有数千行的 WPF DataGrid 的应用程序。我在使用 Vertical ScrollBar 滚动时遇到了性能问题，所以我做了一些研究，发现我可以推迟行的加载，直到通过ScrollViewer.IsDeferredScrollingEnabled = "True"在 DataGrid 中设置完成滚动。一切正常，直到一些用户注意到滚动DataGridComboBoxColumnDataGrid 内的选项列表现在滚动整个DataGrid而不是ComboBox. 仅当您在 ComboBox 滚动条上拖动鼠标时才会发生这种情况，而使用鼠标滚轮滚动时不会发生这种情况。

我使用 .net 4.0 在 vb 中整理了一个示例类，它将说明当使用鼠标拖动滚动 Column 中的 ComboBox 时出现的问题。

XAML

<Window x:Class="MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow" Height="279" Width="496">
<Grid>
    <DataGrid AutoGenerateColumns="False" Height="209" HorizontalAlignment="Left" Margin="12,12,0,0" Name="DataGrid1" VerticalAlignment="Top" Width="448" ItemsSource="{Binding}" ScrollViewer.IsDeferredScrollingEnabled="True">
        <DataGrid.Columns>
            <DataGridTextColumn Binding="{Binding Path=Name}" Header="Name" />
            <DataGridComboBoxColumn Header="Drag Scroll through Items in a cell below" x:Name="IssueComboBoxColumn" />
        </DataGrid.Columns>
    </DataGrid>
</Grid>

代码

Class MainWindow 

Public Sub New()

    ' This call is required by the designer.
    InitializeComponent()

    ' Add any initialization after the InitializeComponent() call.
    Dim sourceList As New List(Of itemExample)
    For i As Integer = 0 To 50
        sourceList.Add(New itemExample("Item" & i.ToString, 4))
    Next

    Dim comboList As New List(Of String)
    For i As Integer = 0 To 50
        comboList.Add("Drop Item " & i.ToString)
    Next

    DataGrid1.DataContext = sourceList
    IssueComboBoxColumn.ItemsSource = comboList
    IssueComboBoxColumn.SelectedValuePath = "ComboItem"
End Sub

Private Class itemExample
    Property Name As String
    Property ComboItem As Integer


    Public Sub New(name As String, comboItem As Integer)
        Me.Name = name
        Me.ComboItem = comboItem
    End Sub
End Class
End Class
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