WPF-支持异步操做的ObservableCollection-AsyncObservableCollection

 

在进行WPF开发过程当中，须要从一个新的线程中操做ObservableCollection,结果程序抛出一个NotSupportedException的错误

 

public class AsyncObservableCollection<T> : ObservableCollection<T>
{
    //获取当前线程的SynchronizationContext对象
    private SynchronizationContext _synchronizationContext = SynchronizationContext.Current;
    public AsyncObservableCollection() { }
    public AsyncObservableCollection(IEnumerable<T> list) : base(list) { }
    protected override void OnCollectionChanged(NotifyCollectionChangedEventArgs e)
    {
          
        if (SynchronizationContext.Current == _synchronizationContext)
        {
            //若是操做发生在同一个线程中，不须要进行跨线程执行         
            RaiseCollectionChanged(e);
        }
        else
        {
            //若是不是发生在同一个线程中
            //准确说来，这里是在一个非UI线程中，须要进行UI的更新所进行的操做         
            _synchronizationContext.Post(RaiseCollectionChanged, e);
        }
    }
    private void RaiseCollectionChanged(object param)
    {
        // 执行         
        base.OnCollectionChanged((NotifyCollectionChangedEventArgs)param);
    }
    protected override void OnPropertyChanged(PropertyChangedEventArgs e)
    {
        if (SynchronizationContext.Current == _synchronizationContext)
        {
            // Execute the PropertyChanged event on the current thread             
            RaisePropertyChanged(e);
        }
        else
        {
            // Post the PropertyChanged event on the creator thread             
            _synchronizationContext.Post(RaisePropertyChanged, e);
        }
    }
    private void RaisePropertyChanged(object param)
    {
        // We are in the creator thread, call the base implementation directly         
        base.OnPropertyChanged((PropertyChangedEventArgs)param);
    }
}

View Code

 

https://blog.csdn.net/juns6/article/details/50964496