Question

我想通过仅从集合中推导出包含ObservableCollection的Object来引用它。如何在C＃中完成？

实施例

public class Order: INotifyPropertyChanged
{   

    public DateTime OrderDate {get; set;}  

    public ObservableCollection<Item> ItemsA {get; set;}

    public ObservableCollection<Item> ItemsB {get; set;}

    public ObservableCollection<Item> ItemsC {get; set;}

 }

代码中的参考

private void ItemsChanged(ObservableCollection<Item> items)
{
    Order newOrder = items.Parent(); // <-- How can this be done?

    if (newOrder.OrderDate <= new DateTime (2016, 6, 30)
    {

    }
}

谢谢！

Answer 1

如何扩展ObservableCollection ??

public ChildObservableCollection<T> : ObservableCollection<T>
{
    private Order parent { get;set;}
}

用法：

public class Order: INotifyPropertyChanged
{   
    public Order()
    {
       ItemsA = new ChildOberservableCollection<Item>();
       ItemsA.parent = this;
       ...
    }

    public DateTime OrderDate {get; set;}  

    public ChildObservableCollection<Item> ItemsA {get; set;}

    public ChildObservableCollection<Item> ItemsB {get; set;}

    public ChildObservableCollection<Item> ItemsC {get; set;}

}

代码中的引用：

private void ItemsChanged(ChildObservableCollection<Item> items)
{
    Order newOrder = items.parent; // done!

    if (newOrder.OrderDate <= new DateTime (2016, 6, 30)
    {

    }
}

Answer 2

我刚刚提出了一种linq方法，在某些情况下也会有所帮助：

(from order in orders
from itemA in order.ItemsA
select new { o = order.Date, i = itemA.ID }).ToList())

获取ObservableCollection的父级

2 个答案: