c#-特殊的集合-可观察的集合-ObservableCollectiony-简单实验

本文介绍了如何使用C#的ObservableCollection进行字符串的添加、插入、删除操作，并通过CollectionChanged事件实时监听并打印变化。通过实例展示了`dataChenge`方法对旧项和新项的处理。

1.概要

using System.Collections.ObjectModel;

ObservableCollection<string> vs = new ObservableCollection<string>();
vs.CollectionChanged += dataChenge;

vs.Add("one");

2代码

using System;
using System.Collections;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Collections.Specialized;

namespace ConsoleApp11
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("Hello World!");
            ObservableCollection<string> vs = new ObservableCollection<string>();
            vs.CollectionChanged += dataChenge;
            vs.Add("one");
            vs.Add("two");
            vs.Insert(1, "three");
            vs.Remove("one");
            Console.ReadKey();
        }
        public static void dataChenge(object sender, NotifyCollectionChangedEventArgs e) {
            Console.WriteLine(e.Action.ToString());
            if (e.OldItems != null) {
                Console.Write("e.OldItems:");
                foreach (var item in e.OldItems) {
                    Console.WriteLine(item);
                }
            }
            if (e.NewItems != null)
            {
                Console.Write("e.NewItems:");
                foreach (var item in e.NewItems)
                {
                    Console.WriteLine(item);
                }
            }
        } 
    }
}

运行结果