用于 c# 的 ObservableDictionary [英] ObservableDictionary for c#

问题描述

我正在尝试使用 ObservableDictionary 的以下实现:ObservableDictionary (C#).

I'm trying to use following implementation of the ObservableDictionary: ObservableDictionary (C#).

当我在将字典绑定到 DataGrid 时使用以下代码时:

When I'm using following code while binding the dictionary to a DataGrid:

ObserveableDictionary<string,string> dd=new ObserveableDictionary<string,string>();
....
dd["aa"]="bb";
....
dd["aa"]="cc";

在 dd["aa"]="cc"; 我收到以下异常

Index was out of range. Must be non-negative and less than the size of the 
collection. Parameter name: index

这个异常是在CollectionChanged(this, new NotifyCollectionChangedEventArgs(action, newItem, oldItem)中抛出的，方法如下:

This exception is thrown in CollectionChanged(this, new NotifyCollectionChangedEventArgs(action, newItem, oldItem) in the following method:

private void OnCollectionChanged(NotifyCollectionChangedAction action, KeyValuePair<TKey, TValue> newItem, KeyValuePair<TKey, TValue> oldItem)
{
  OnPropertyChanged();

  if (CollectionChanged != null) CollectionChanged(this, new NotifyCollectionChangedEventArgs(action, newItem, oldItem));
}

index 参数似乎对应于 KeyValuePair旧项目.

KeyValuePair 怎么会超出范围，我应该怎么做才能使它起作用?

How can KeyValuePair<TKey, TValue> be out of range, and what should I do to make this work?

推荐答案

类似的数据结构，绑定到Dictionary类型的集合

Similar data structure, to bind to Dictionary type collection

http://drwpf.com/blog/2007/09/16/can-i-bind-my-itemscontrol-to-a-dictionary/

它提供了一个新的数据结构 ObservableDictionary 并触发 PropertyChanged 基础字典有任何变化.

It provides a new Data structure ObservableDictionary and fires PropertyChanged in case of any change to underlying Dictionary.

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