WPF 中的自动完成文本框

使用WPF中的自动完成文本框可以为用户提供更加便捷的输入体验。自动完成文本框是一种可以根据用户输入的文本内容自动匹配并显示可能的选项的控件。它可以用于各种场景，例如输入搜索关键词、选择城市、选择联系人等。

xaml

csharp
public partial class MainWindow : Window
{
    private List autoCompleteOptions = new List
    {
        "Apple",
        "Banana",
        "Cherry",
        "Durian",
        "Grape",
        "Lemon",
        "Orange",
        "Peach",
        "Strawberry",
        "Watermelon"
    };
    public MainWindow()
    {
        InitializeComponent();
        txtAutoComplete.TextChanged += TxtAutoComplete_TextChanged;
    }
    private void TxtAutoComplete_TextChanged(object sender, TextChangedEventArgs e)
    {
        string userInput = txtAutoComplete.Text;
        List filteredOptions = autoCompleteOptions.Where(option => option.StartsWith(userInput, StringComparison.OrdinalIgnoreCase)).ToList();
        if (filteredOptions.Count > 0)
        {
            txtAutoComplete.ItemsSource = filteredOptions;
            txtAutoComplete.IsDropDownOpen = true;
        }
        else
        {
            txtAutoComplete.IsDropDownOpen = false;
        }
    }
}