WPF 简单实现下拉筛选控件

框架使用.NET40；

(相关资料图)

Visual Studio 2022;

使用ICollectionView[2]实现筛选功能，还支持其他如下：

实现代码

1）CheckedSearch.cs代码如下：

using System.Collections.ObjectModel;
using System.ComponentModel;
using System.Linq;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using WpfCustomControlLibrary1.Datas;

namespace WpfCustomControlLibrary1
{
    public class CheckedSearch : Control
    {
        private ICollectionView _filteredCollection;
        public ICollectionView FilteredCollection { get { return _filteredCollection; } }

        private string _searchText = string.Empty;
        public string SearchText
        {
            get { return _searchText; }
            set
            {
                if (_searchText != value)
                {
                    _searchText = value;
                    _filteredCollection.Refresh();
                }
            }
        }

        public string Text
        {
            get { return (string)GetValue(TextProperty); }
            set { SetValue(TextProperty, value); }
        }

        public static readonly DependencyProperty TextProperty =
            DependencyProperty.Register("Text", typeof(string), typeof(CheckedSearch), new PropertyMetadata(string.Empty));


        public ObservableCollection ItemsSource
        {
            get { return (ObservableCollection)GetValue(ItemsSourceProperty); }
            set { SetValue(ItemsSourceProperty, value); }
        }

        public static readonly DependencyProperty ItemsSourceProperty =
            DependencyProperty.Register("ItemsSource", typeof(ObservableCollection), typeof(CheckedSearch), new PropertyMetadata(null, OnItemsSourceChanged));

        private static void OnItemsSourceChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            var choseSearch = (CheckedSearch)d;
            if (choseSearch == null) return;
            if (choseSearch._filteredCollection == null && choseSearch.ItemsSource.Count > 0)
            {
                foreach (var item in choseSearch.ItemsSource)
                {
                    item.PropertyChanged -= choseSearch.Item_PropertyChanged;
                    item.PropertyChanged += choseSearch.Item_PropertyChanged;
                }
                choseSearch._filteredCollection = CollectionViewSource.GetDefaultView(choseSearch.ItemsSource);
                choseSearch._filteredCollection.Filter = choseSearch.ContainsFilter;
            }
        }
        string GetItems()
        {
            var list = ItemsSource.Where(x=>x.IsChecked).Select(x=>x.Name).ToList();
            var visibleItems = string.Join("^",list);
            return visibleItems;
        }
        static CheckedSearch()
        {
            DefaultStyleKeyProperty.OverrideMetadata(typeof(CheckedSearch), new FrameworkPropertyMetadata(typeof(CheckedSearch)));
        }

        private void Item_PropertyChanged(object sender, PropertyChangedEventArgs e)
        {
            if (e.PropertyName == "IsChecked")
                Text = GetItems();
            
        }

        private bool ContainsFilter(object item)
        {
            var model = item as CheckedSearchItem;
            if (model == null)
                return false;
            if (string.IsNullOrEmpty(SearchText))
                return true;
            if (model.Name.ToUpperInvariant().Contains(SearchText.ToUpperInvariant()))
                return true;
            return false;
        }
    }
}

2）CheckedSearchItem.cs代码如下：

using System.ComponentModel;

namespace WpfCustomControlLibrary1.Datas
{
    public class CheckedSearchItem
    {
        public string Name { get; set; }

        private bool _isChecked;
        public bool IsChecked
        {
            get { return _isChecked; }
            set
            {
                _isChecked = value;
                OnPropertyChanged("IsChecked");
            }
        }
        
        public event PropertyChangedEventHandler PropertyChanged;
        protected void OnPropertyChanged(string propertyName)
        {
            if (PropertyChanged != null)
                PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
        }

    }
}

3）CheckedSearch.xaml代码如下：

4）CheckedSearchExample.xaml示例代码如下：

5）CheckedSearchExample.xaml数据源示例代码如下：

using System.Collections.ObjectModel;
using System.Windows;
using WpfCustomControlLibrary1.Datas;

namespace WpfApp1
{
    public partial class MainWindow
    {
        public ObservableCollection ItemsSource
        {
            get { return (ObservableCollection)GetValue(ItemsSourceProperty); }
            set { SetValue(ItemsSourceProperty, value); }
        }

        public static readonly DependencyProperty ItemsSourceProperty =
            DependencyProperty.Register("ItemsSource", typeof(ObservableCollection), typeof(MainWindow), new PropertyMetadata(null));


        public MainWindow()
        {
            InitializeComponent();
            Loaded += MainWindow_Loaded;
        }

        private void MainWindow_Loaded(object sender, RoutedEventArgs e)
        {

            ItemsSource = new ObservableCollection();
            var items = new ObservableCollection();
            items.Add(new CheckedSearchItem { Name = "Winform" });
            items.Add(new CheckedSearchItem { Name = "WPF" });
            items.Add(new CheckedSearchItem { Name = "WinUI 3" });
            items.Add(new CheckedSearchItem { Name = "MAUI" });
            items.Add(new CheckedSearchItem { Name = "Avalonia UI" });
            ItemsSource = items;
        }
    }
}

到此这篇关于基于WPF实现简单的下拉筛选控件的文章就介绍到这了,更多相关WPF下拉筛选控件内容请搜索脚本之家以前的文章或继续浏览下面的相关文章希望大家以后多多支持脚本之家！

关键词：