按值类型的ObservableCollection [英] ObservableCollection by Value Type

问题描述

我认为Code解释了我的问题

I think Code explains my problem

public ObservableCollection<Project> Project { get; set; }

 private Project _current;

    public Project Current
    {
        get { return _current; }
        set
        {
            if (_current== value)
            {
                return;
            }
            _current= value;
            NotifyOfPropertyChange(() => Current);
        }
    }

点击按钮点击

On a button Click

public void SelectPump()
   {
       Project.Add(Current);
       for (var i = 0; i < Project.Count; i++)
       {
           Project[i].IdNo = i;
       }
   }

如果我的Project.Count（）= 3，我所有的项目[i] .IdNo都会变为3希望它是

All my Project[i].IdNo is becoming 3 if my Project.Count() =3 I want it to be

Project[0].IdNo = 0;
Project[1].IdNo = 1;
Project[2].IdNo = 2;

推荐答案

代码示例：尝试根据此情况重新调整代码，看看会发生什么。

Code example: Just try to refacoter your code based on this and see what happens.

class FooObservableCollection : ObservableCollection<Foo>
{
    protected override void InsertItem(int index, Foo item)
    {
        base.Add(index, Foo);

        if (this.CollectionChanged != null)
            this.CollectionChanged(this, new NotifyCollectionChangedEventArgs (NotifyCollectionChangedAction.Add, item, index);
    }
}

var collection = new FooObservableCollection();
collection.CollectionChanged += CollectionChanged;

collection.Add(new Foo());

void CollectionChanged (object sender, NotifyCollectionChangedEventArgs e)
{
    Foo newItem = e.NewItems.OfType<Foo>().First();
}

这篇关于按值类型的ObservableCollection的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！