关于c＃：在枚举时修改了Collection


Collection was modified while enumeration

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Possible Duplicate:
Collection was modified; enumeration operation may not execute

我有一个通用列表，在其中枚举时执行一些操作。

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foreach(Action<string> action in actionList)
{
    if(action != null) {
        action(mystring);
    }
}

现在我得到这个例外：

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InvalidOperationException:
Collection was modified; enumeration operation may not execute

如何解决这个问题？我被紧紧地钉在.NET 3.5上：/

相关讨论

好presumably one of the actions modifies actionList，invalidating the迭代器。the Way to the error is扩avoid to take a copy of the list的第一，例如P＞＜／

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foreach(Action<string> action in actionList.ToList())
{
    if(action != null) {
        action(mystring);                              
    }
}

或是：P＞＜／

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foreach (var action in actionList.Where(action => action != null).ToList())
{
    action(mystring);
}
相关讨论

你在网上actionlist修饰the the迭代它。它是在第二个线程which is not with a synchronized method which the action or电流回路改造or another make the迭代。我的解决方案是：theP＞＜／

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var tmp = new List<Action<string> >(actionList);
foreach(Action<string> action in tmp)
{
    if(action != null) {
      action(mystring);                              
    }
}

但它只会工作在房屋的房屋action' modification of You should并行线程在synchronize of the list。P＞＜／

相关讨论