blocks|key|719010|text|执行逆操作，创建一个新列表：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|719011|List+myFilteredList+=+new+List();
foreach+(MyObject+myObject+in+myListOfMyObjects)
{
+++++if+(!condition)+myFilteredList.Add(myObject);
}|code-block|syntax|javascript|719012|然后在需要的地方使用新的列表。|719013|您也可以轻松地使用LINQ表达式，再一次，逆条件。这有一个额外的好处，即不创建一个新结构，但也存在一个懒散枚举的缺陷：|719014|var+myFilteredList+=+from+myObject+in+myListOfMyObjects
+++++++++++++++++++++where+!condition
+++++++++++++++++++++select+myObject;|719015|但是，如果您确实需要从列表中删除项目，我通常使用“创建一个新列表，然后重申和删除”方法。|719016|entityMap^0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|S|8|@]|9|@]|A|$]]|$1|I|3|J|5|6|7|T|8|@]|9|@]|A|$]]|$1|K|3|L|5|D|7|U|8|@]|9|@]|A|$E|F]]|$1|M|3|N|5|6|7|V|8|@]|9|@]|A|$]]|$1|O|3|-4|5|6|7|W|8|@]|9|@]|A|$]]]|P|$]]

Do the inverse, creating a new list:

<pre><code>List myFilteredList = new List();
foreach (MyObject myObject in myListOfMyObjects)
{
 if (!condition) myFilteredList.Add(myObject);
}
</code></pre>

Then use the new list wherever you need it. 

You can also use a LINQ expression easily, again, inversing the condition. This has the added benefit of not creating a new structure, but also the pitfalls of it being a lazy enumerable:

<pre><code>var myFilteredList = from myObject in myListOfMyObjects
 where !condition
 select myObject;
</code></pre>

However, if you truly need to remove the items from the list, I typically use the "create a new list, then reiterate and remove" approach.

blocks|key|355714|text|我不喜欢反向循环的想法，因为这只适用于某些数据结构。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|355715|通常，我会使用第二种技术，并将要删除的项目累积到单独的“要删除的”集合中。如果删除会导致现有的迭代无效(例如，任何平衡的树集合都会发生这种情况)，那么我看不出有什么解决办法。|355716|我偶尔使用的其他技术是在找到要删除的第一个元素时重新启动整个迭代。如果您在没有找到要删除的任何项的情况下完成了它，那么函数就完成了。这是低效的，但有时，如果从集合中删除一个项可能会更改需要删除的一组项，则有时是必要的。|355717|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|H|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|I|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|J|8|@]|9|@]|A|$]]|$1|F|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|G|$]]

I don't like the reversed for loop idea, since that only works on certain data structures. 

In general I'd use the second technique and accumulate the items to be deleted in a separate 'to-be-deleted' collection. If deletion can cause existing iterates to be invalidated (as will happen with any balanced tree collection for example) then I don't see a way around this.

The only other technique that I've occasionally used is to restart the whole iteration when you find the first element to delete. If you make it through without finding any items to delete then the function is finished. This is inefficient, but sometimes neccessary if deleting one item from the collection may change the set of items that need to be deleted.

blocks|key|354111|text|有一个有用的List<T>.RemoveAll(Predicate<T>+match)方法，我认为它是为此而设计的：http://msdn.microsoft.com/en-us/library/wdka673a.aspx|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|354112|entityMap|0|LINK|mutability|MUTABLE|url|http://msdn.microsoft.com/en-us/library/wdka673a.aspx^0|6|11|1M|1H|0|0^^$0|@$1|2|3|4|5|6|7|N|8|@$9|O|A|P|B|C]]|D|@$9|Q|A|R|1|S]]|E|$]]|$1|F|3|-4|5|6|7|T|8|@]|D|@]|E|$]]]|G|$H|$5|I|J|K|E|$L|M]]]]

There's a useful <code>List&lt;T&gt;.RemoveAll(Predicate&lt;T&gt; match)</code> method which I think is designed for this: <a href="http://msdn.microsoft.com/en-us/library/wdka673a.aspx" rel="noreferrer">http://msdn.microsoft.com/en-us/library/wdka673a.aspx</a>

blocks|key|719103|text|这有点简单，但当我计划从IEnumerable/IList中删除项目时，我通常只需复制：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|719104|foreach+(MyObject+myObject+in+new+List<MyObject>(MyListOfMyObjects))
{
+++++if+(condition)+MyListOfMyObjects.Remove(myObject);
}|code-block|syntax|javascript|719105|这不是最有效的方法，但很容易读懂。过早的优化等等。|719106|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

It's kind of simple-minded, but when I plan to delete items from an IEnumerable/IList I usually just make a copy:

<pre><code>foreach (MyObject myObject in new List&lt;MyObject&gt;(MyListOfMyObjects))
{
 if (condition) MyListOfMyObjects.Remove(myObject);
}
</code></pre>

It's not the most efficient way to do it, but it's easy to read. Premature optimization and all that.

blocks|key|705552|text|我很感激这件事现在可能已经死了，但我一直这样做的方式是：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|705553|myObject+myObject+in+MyListOfMyObjects|705554|{|705555|若(条件)+MyListOfMyObjects.Remove(myObject)；|705556|中断；|offset|length|style|BOLD|705557|}|705558|对象被移除，然后循环退出，中提琴！|705559|entityMap^0|0|0|0|0|0|3|0|0|0^^$0|@$1|2|3|4|5|6|7|T|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|U|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|V|8|@]|9|@]|A|$]]|$1|F|3|G|5|6|7|W|8|@]|9|@]|A|$]]|$1|H|3|I|5|6|7|X|8|@$J|Y|K|Z|L|M]]|9|@]|A|$]]|$1|N|3|O|5|6|7|10|8|@]|9|@]|A|$]]|$1|P|3|Q|5|6|7|11|8|@]|9|@]|A|$]]|$1|R|3|-4|5|6|7|12|8|@]|9|@]|A|$]]]|S|$]]

I appreciate this may be dead now but the way I always do this is:

foreach (MyObject myObject in MyListOfMyObjects) 
 
{

if (condition) MyListOfMyObjects.Remove(myObject);

break;

} 

Object is removed and then loop exits, viola!

blocks|key|354146|text|我刚看到这篇文章，想和大家分享一下。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|354147|void+RemoveAll(object+condition)++
{

++++bool+found+=+false;

++++foreach(object+thisObject+in+objects)++++
++++{

++++++++if+(condition)++++
++++++++{++++
++++++++++++objects.Remove(thisObject);

++++++++++++found+=+true;

++++++++++++break;+//exit+loop++++
++++++++}+++++
+++++}

++++//+Call+again+recursively

++++if+(found)+RemoveAll(condition);

}|code-block|syntax|javascript|354148|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

I just came across this post and thought I would share.

<pre><code>void RemoveAll(object condition) 
{

 bool found = false;

 foreach(object thisObject in objects) 
 {

 if (condition) 
 { 
 objects.Remove(thisObject);

 found = true;

 break; //exit loop 
 } 
 }

 // Call again recursively

 if (found) RemoveAll(condition);

}
</code></pre>

blocks|key|354161|text|我有一本字典，想要处理所有的值。当每个值被释放时，它会从字典中移除自己，从而产生您所讨论的问题。我做了以下工作：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|354162|foreach+(var+o+in+dictionary.Values.ToList())
{
++o.Dispose();
}|code-block|syntax|javascript|354163|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

I have a dictionary and want to Dispose of all Values. When each value is disposed it removes itself from the dictionary which creates the problem you discuss. I did the following:

<pre><code>foreach (var o in dictionary.Values.ToList())
{
 o.Dispose();
}
</code></pre>

<h2>Duplicate</h2>

<a href="https://stackoverflow.com/questions/308466/modifying-a-collection-while-iterating-through-it-c">Modifying A Collection While Iterating Through It</a>

<hr>

Has anyone a nice pattern to allow me to get around the inability to remove objects while I loop through an enumerable collection (eg, an IList or KeyValuePairs in a dictionary)

For example, the following fails, as it modifies the List being enumerated over during the foreach

<pre><code>foreach (MyObject myObject in MyListOfMyObjects)
{
 if (condition) MyListOfMyObjects.Remove(myObject);
}
</code></pre>

In the past I have used two methods.

I have replaced the foreach with a reversed for loop (so as not to change the any indexes I am looping over if I remove an object).

I have also tried storing a new collection of objects to remove within to loop, then looping through that collection and removed the objects from the original collection.

These work fine, but neither feels nice, and I was wondering if anyone has come up with a more elegant solution to the issue

How to remove objects from an Enumerable collection in a loop

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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复制有谁有一个很好的模式可以让我在循环遍历可枚举集合(例如字典中的IList或KeyValuePairs )时，避免无法删除对象的问题。例如，以下内容失败，因为它修改了在foreach期间正在枚举的列表foreach (MyObject myObject in MyListOfMyObjects){     if (c...

问如何从循环中的可枚举集合中移除对象
EN

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