wpf 简单实验 数据更新 列表更新

1.概要

1.1 需求

一个列表提供添加修改删除的功能，添加和修改的内容都来自一个输入框

1.2 要点

• DisplayMemberPath="Zhi"
• 列表.ItemsSource = datalist;
• (列表.SelectedItem != null)
• (列表.SelectedItem as A).Zhi = 内容.Text;
• datalist.Remove((列表.SelectedItem as A)!);
• public String? Zhi { get { return _zhi; } set { _zhi = value; OnPropertyChanged(nameof(Zhi)); } }
• PropertyChanged.Invoke(this, new PropertyChangedEventArgs(name));

2.代码

2.1 xaml

<Window x:Class="WpfApp5.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:WpfApp5"
        mc:Ignorable="d"
        Title="MainWindow" Height="450" Width="800">
    <StackPanel>
        <TextBox Name="内容" ></TextBox>
        <Button Name="Add" Content="添加" Click="Add_Click" />
        <Button Name="Update" Content="修改" Click="Update_Click" />
        <Button Name="Delete" Content="删除" Click="Delete_Click" />
        <ListBox Name="列表" DisplayMemberPath="Zhi" Height="100"></ListBox>
    </StackPanel>
</Window>

2.2 代码

using System.Collections.ObjectModel;
using System.ComponentModel;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;

namespace WpfApp5
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// 连表数据绑定
    /// </summary>
    public partial class MainWindow : Window
    {
        ObservableCollection<A> datalist = new ObservableCollection<A>();
        //List<A> datalist = new List<A>();

        public MainWindow()
        {
            InitializeComponent();
            init();
        }
        private void init()
        {
            datalist.Add(new A { Zhi = "1" });
            datalist.Add(new A { Zhi = "2" });
            datalist.Add(new A { Zhi = "3" });
            //列表.DataContext = datalist;
            列表.ItemsSource = datalist;
        }

        private void Add_Click(object sender, RoutedEventArgs e)
        {
            datalist.Add(new A { Zhi = 内容.Text });
        }

        private void Update_Click(object sender, RoutedEventArgs e)
        {
            if (列表.SelectedItem != null)
            {
                (列表.SelectedItem as A).Zhi = 内容.Text;
            }
        }

        private void Delete_Click(object sender, RoutedEventArgs e)
        {
            if (列表.SelectedItem != null)
            {
                datalist.Remove((列表.SelectedItem as A)!);
            }
        }
    }
    class A:INotifyPropertyChanged
    {
        private String? _zhi;
        public String? Zhi { get { return _zhi; } set { _zhi = value; OnPropertyChanged(nameof(Zhi)); } }

        public event PropertyChangedEventHandler? PropertyChanged;
        private void OnPropertyChanged(String name)
        {
            if (PropertyChanged != null)
            {
                PropertyChanged.Invoke(this, new PropertyChangedEventArgs(name));
            }
        }
    }
}

3.运行结果