函数不会改变传递的指针 C++

Function does not change passed pointer C++(函数不会改变传递的指针 C++)
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问题描述

我有我的函数,我正在那里填充targetBubble,但是在调用这个函数之后它没有被填充,但是我知道它被填充在这个函数中,因为我有输出代码.

I have my function and I am filling targetBubble there, but it is not filled after calling this function, but I know it was filled in this function because I have there output code.

bool clickOnBubble(sf::Vector2i & mousePos, std::vector<Bubble *> bubbles, Bubble * targetBubble) {
    targetBubble = bubbles[i];
}

我像这样传递指针

Bubble * targetBubble = NULL;
clickOnBubble(mousePos, bubbles, targetBubble);

为什么它不起作用?

推荐答案

因为您正在传递指针的副本.要更改指针,您需要这样的东西:

Because you are passing a copy of pointer. To change the pointer you need something like this:

void foo(int **ptr) //pointer to pointer
{
    *ptr = new int[10]; //just for example, use RAII in a real world
}

void bar(int *& ptr) //reference to pointer (a bit confusing look)
{
    ptr = new int[10];
}

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