我有一节范例课。它有一个附加了事件处理程序的ObservableCollection。
class SomeItem
{
public ObservableCollection<Thing> Things = new ObservableCollection<Thing>();
private SomeEventHandler(object Sender, NotifyCollectionChangedEventArgs E)
{
//do something
}
public SomeItem()
{
this.Things.CollectionChanged += SomeEventHandler;
}
}
我正在执行以下代码：
SomeItem Instance = new SomeItem();
Instance.Things.Add(new Thing()); // SomeEventHandler executed;
SomeItem AnotherReference = Instance;
AnotherReference.Things.Add(new Thing()); // SomeEventHandler NOT executed
如果从AnotherReference访问集合，为什么不执行事件处理程序？
我无法再现问题。这段代码按预期工作。
using System;
using System.Collections.ObjectModel;
using System.Collections.Specialized;
namespace ConsoleApp2
{
class Program
{
static void Main(string[] args) {
SomeItem Instance = new SomeItem();
Instance.Things.Add(new Thing()); // SomeEventHandler executed;
SomeItem AnotherReference = Instance;
AnotherReference.Things.Add(new Thing()); // SomeEventHandler ALSO executed
}
}
class Thing {
}
class SomeItem
{
public ObservableCollection<Thing> Things = new ObservableCollection<Thing>();
private void SomeEventHandler(object sender, NotifyCollectionChangedEventArgs e) {
Console.WriteLine("Hello from SomeEventHandler");
}
public SomeItem() {
this.Things.CollectionChanged += SomeEventHandler;
}
}
}
结果：
Hello from SomeEventHandler
Hello from SomeEventHandler
Press any key to continue.
