删除映射中的特定条目，但迭代器必须指向删除后的下一个元素 [英] delete a specific entry in the map,but the iterator must point to the next element after the deletion

问题描述

如何从stdmap

我有一个地图 map1< string，vector< string> ; 我有一个迭代器为这个地图itr。
我想删除itr指向的地图中的条目。
我可以使用函数map1.erase（itr）;在这行之后迭代器itr变得无效。
根据我的项目中的要求，迭代器必须指向下一个元素。可以任何身体帮助我regerding这
提前:)
santhosh

I have a map map1<string,vector<string>> i have a iterator for this map "itr". i want to delete the entry from this map which is pointed by "itr". i can use the function map1.erase(itr); after this line the iterator "itr" becomes invalid. as per my requirement in my project,the iterator must point to the next element. can any body help me regerding this thans in advance:) santhosh

推荐答案

递增迭代器，同时将其作为参数进行擦除：

You can post-increment the iterator while passing it as argument to erase:

myMap.erase(itr++)

这样，删除前由 itr 指向的元素迭代器增加以指向映射中的下一个元素。

This way, the element that was pointed by itr before the erase is deleted, and the iterator is incremented to point to the next element in the map. If you're doing this in a loop, beware not to increment the iterator twice.

另请参阅此回答来自类似问题，或已回应这个问题。

See also this answer from a similar question, or what has been responded to this question.

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