安全删除 ForEach 中的 DataRow [英] Safely Removing DataRow In ForEach

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本文介绍了安全删除 ForEach 中的 DataRow的处理方法,对大家解决问题具有一定的参考价值,需要的朋友们下面随着小编来一起学习吧!

问题描述

我不明白为什么这段代码不起作用.

I don't understand why this code does not work.

foreach (DataRow dataRow in dataTable.Rows)
{
    if (true)
    {
        dataRow.Delete();
    }
}

推荐答案

即使 DataRow.Delete 不修改集合的状态,Microsoft 文档 指出在迭代合集:

Even though DataRow.Delete doesn't modify the state of the collection, Microsoft documentation states that you shouldn't call it while iterating over the collection:

在遍历 DataRowCollection 对象时,不应在 foreach 循环中调用 Delete 和 Remove.Delete 或 Remove 修改集合的状态.

Neither Delete nor Remove should be called in a foreach loop while iterating through a DataRowCollection object. Delete nor Remove modify the state of the collection.

最好的解决方案通常是为要删除的项目创建一个单独的集合(例如 List),然后在删除它们之后 完成迭代.

The best solution is usually to create a separate collection (e.g. a List<DataRow>) of items you want to remove, and then remove them after you've finished iterating.

这也是您想要从集合中删除项目的解决方案,因为 .NET 中的大多数集合不允许您在迭代时更改集合的内容.

This is also the solution for situations where you want to remove items from a collection, as most collections in .NET don't allow you to change the contents of the collection while you're iterating over it.

这篇关于安全删除 ForEach 中的 DataRow的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持IT屋!

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