WPF 自定义一个下拉框类下拉框里有分列输入框能模糊查询并且把模糊查询的显示在下拉框可以有几万行数据

以下是一个简单的自定义下拉框类，包含分列、模糊查询和大量数据：

public class CustomComboBox : ComboBox
{
    private TextBox _searchBox;
    private ListView _listView;
    private GridView _gridView;

    public CustomComboBox()
    {
        // 创建搜索框和列表视图
        _searchBox = new TextBox();
        _listView = new ListView();
        _gridView = new GridView();

        // 设置搜索框样式
        _searchBox.Margin = new Thickness(2);
        _searchBox.TextChanged += SearchBox_TextChanged;

        // 设置列表视图样式
        _listView.Margin = new Thickness(2);
        _listView.View = _gridView;

        // 绑定下拉框的数据源和显示成员
        ItemsSource = GetData();
        DisplayMemberPath = "Name";

        // 将搜索框和列表视图添加到下拉框中
        StackPanel stackPanel = new StackPanel();
        stackPanel.Children.Add(_searchBox);
        stackPanel.Children.Add(_listView);
        Popup popup = Template.FindName("PART_Popup", this) as Popup;
        popup.Child = stackPanel;
    }

    // 获取数据源
    private List<Item> GetData()
    {
        List<Item> items = new List<Item>();
        for (int i = 0; i < 10000; i++)
        {
            items.Add(new Item { Id = i, Name = "Item " + i });
        }
        return items;
    }

    // 模糊查询
    private void SearchBox_TextChanged(object sender, TextChangedEventArgs e)
    {
        string searchText = _searchBox.Text.Trim().ToLower();
        if (searchText == "")
        {
            _listView.ItemsSource = ItemsSource;
            return;
        }

        List<Item> filteredItems = new List<Item>();
        foreach (Item item in ItemsSource)
        {
            if (item.Name.ToLower().Contains(searchText))
            {
                filteredItems.Add(item);
            }
        }
        _listView.ItemsSource = filteredItems;
    }

    // 分列
    public void AddColumn(string header, string bindingPath, int width)
    {
        GridViewColumn column = new GridViewColumn();
        column.Header = header;
        column.DisplayMemberBinding = new Binding(bindingPath);
        column.Width = width;
        _gridView.Columns.Add(column);
    }

    // 数据项类
    private class Item
    {
        public int Id { get; set; }
        public string Name { get; set; }
    }
}

使用方法：

<local:CustomComboBox Width="200" Height="30">
    <local:CustomComboBox.Style>
        <Style TargetType="{x:Type local:CustomComboBox}">
            <Setter Property="Template">
                <Setter.Value>
                    <ControlTemplate TargetType="{x:Type local:CustomComboBox}">
                        <Grid>
                            <ToggleButton x:Name="ToggleButton" Template="{StaticResource ComboBoxToggleButton}" Grid.Column="2" Focusable="false" IsChecked="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}" ClickMode="Press"/>
                            <ContentPresenter x:Name="ContentSite" IsHitTestVisible="False" Content="{TemplateBinding SelectionBoxItem}" ContentTemplate="{TemplateBinding SelectionBoxItemTemplate}" ContentTemplateSelector="{TemplateBinding ItemTemplateSelector}" VerticalAlignment="Center" Margin="3,3,23,3" />
                            <TextBox x:Name="PART_EditableTextBox" Style="{x:Null}" Template="{StaticResource ComboBoxTextBox}" HorizontalAlignment="Left" VerticalAlignment="Bottom" Margin="3,3,23,3" Focusable="True" Background="Transparent" Visibility="Hidden" IsReadOnly="{TemplateBinding IsReadOnly}"/>
                            <Popup x:Name="Popup" Placement="Bottom" IsOpen="{TemplateBinding IsDropDownOpen}" AllowsTransparency="True" Focusable="False" PopupAnimation="Slide">
                                <Grid x:Name="DropDown" SnapsToDevicePixels="True" MinWidth="{TemplateBinding ActualWidth}" MaxHeight="{TemplateBinding MaxDropDownHeight}">
                                    <Border x:Name="DropDownBorder" Background="{StaticResource WindowBackgroundBrush}" BorderThickness="1" BorderBrush="{StaticResource SolidBorderBrush}"/>
                                    <ScrollViewer Margin="4,6,4,6" SnapsToDevicePixels="True">
                                        <StackPanel IsItemsHost="True" KeyboardNavigation.DirectionalNavigation="Contained"/>
                                    </ScrollViewer>
                                </Grid>
                            </Popup>
                        </Grid>
                        <ControlTemplate.Triggers>
                            <Trigger Property="IsEnabled" Value="False">
                                <Setter TargetName="PART_EditableTextBox" Property="Foreground" Value="{StaticResource DisabledForegroundBrush}"/>
                            </Trigger>
                            <Trigger Property="IsGrouping" Value="True">
                                <Setter Property="ScrollViewer.CanContentScroll" Value="False"/>
                            </Trigger>
                            <Trigger SourceName="Popup" Property="Popup.AllowsTransparency" Value="True">
                                <Setter TargetName="DropDownBorder" Property="CornerRadius" Value="4"/>
                                <Setter TargetName="DropDownBorder" Property="Margin" Value="0,2,0,0"/>
                            </Trigger>
                            <Trigger Property="IsEditable" Value="True">
                                <Setter Property="IsTabStop" Value="False"/>
                                <Setter TargetName="PART_EditableTextBox" Property="Visibility" Value="Visible"/>
                                <Setter TargetName="ContentSite" Property="Visibility" Value="Hidden"/>
                            </Trigger>
                        </ControlTemplate.Triggers>
                    </ControlTemplate>
                </Setter.Value>
            </Setter>
        </Style>
    </local:CustomComboBox.Style>
</local:CustomComboBox>

添加分列：

customComboBox.AddColumn("ID", "Id", 50);
customComboBox.AddColumn("Name", "Name", 150);
``