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removing objects from an array

2012-05-03 17:05  Rollen Holt  阅读(409)  评论(0编辑  收藏  举报

I am creating a program that uses an array of objects declared with

Element* elements =newElement[number];

where an element is a class that has/needs a its own destructor.

when I go to delete this would I use just use array delete, and have the program worry about calling the destructor:

delete[] elements;

or do I call the destructor for each item explicitly with keyword delete:

for(int ii =0; ii<ArraySize; ii++)
    delete elements[ii];
delete[] elements;

Note: I understand that I could probably use something like boost::ptr_vector, but I wanted similar to hashTable functionality (so the for loop would need additional information, but that is outside of the direct scope of this question) which is why I am using a traditional array. I would still like to know which behavior is needed to avoid memory leaks.

解答:

第一个是正确的,第二个会得到编译错误。

这个问题主要的问题其实是对于多位数组的动态内存分配的问题。比如我们不能直接使用int* p=new int[4][3];等的的。

而是应该借鉴下面的例子:

elements = new Element *[rows];
for (int i=0; i<rows; i++)
    elements[i] = new Element[row_len];

  然后采用:

for (int i=0; i<rows; i++)
    delete [] elements[i];
delete [] elements;

  原文地址:http://stackoverflow.com/questions/10425354/removing-objects-from-an-array