如何用IsEditable=false在ComboBox的DropDown中进行文本搜索

<ComboBox IsEditable="False">
    <!-- 添加选项列表 -->
</ComboBox>

<ComboBox IsEditable="False">
    <ComboBoxItem Content="选项1" />
    <ComboBoxItem Content="选项2" />
    <ComboBoxItem Content="选项3" />
</ComboBox>

<ComboBox IsEditable="False" TextChanged="ComboBox_TextChanged">
    <!-- 添加选项列表 -->
</ComboBox>

private void ComboBox_TextChanged(object sender, TextChangedEventArgs e)
{
    ComboBox comboBox = (ComboBox)sender;
    string searchText = comboBox.Text;

    // 根据搜索文本筛选选项
    List<string> filteredOptions = GetFilteredOptions(searchText);

    // 更新ComboBox的选项列表
    comboBox.ItemsSource = filteredOptions;
}