Question

我的班级Person实现了我的界面，ISequenced。

我有一个ObservableCollection＆lt; Person＆gt;我需要传递给一个方法，该方法将IList＆lt; ISequenced＆gt;类型的对象作为参数。我的问题是我如何传递ObservableCollection - 没有复制 - 这样被调用的函数可以修改它。

请注意这个问题的答案：Is there a way to convert an observable collection to regular collection? 演示.ToList（）创建一个新对象。

public interface ISequenced
{
    int Sequence { get; set; }
}


public class Person : ISequenced
{
    public int Sequence {get; set;}
    //...
}

public class MyCode
{
    public ObservableCollection<Person> Entities {get; set;}
    public Person CurrentItem {get;set;}


    private void MoveDown()
    {
        IEnumerable<ISequenced> seq = Entities.Cast<ISequenced>(); // works but we need IList not IEnumerable
        IList<Person> p = (IList<Person>)Entities;                  //  works but we need IList ISequenced
        IList<ISequenced> pp = (IList<ISequenced>)p;                // throws

        // Need to pass a reference to Entities.... throws unable to cast here
        Sequencer.SequenceDown((IList<ISequenced>)Entities, CurrentItem as ISequenced);

    }
}

public static class Sequencer
{
    public static void SequenceDown(IList<ISequenced> items, ISequenced currentItem)
    {
        // swap the positions of two elements in the collection here
    }
}

如何构建ObservableCollection <t>，其中T将ISomething实现为IList <isomething>

0 个答案: