c + +删除动态数组的对象 [英] C++ Delete Objects of dynamic Array

问题描述

我从Embarcadero.I的C ++ Builder的编程创建的TImage数组：

I am programming with the C++ Builder from Embarcadero.I created an TImage Array :

TImage *Image[c] ; // c is 5 

after that I am creating dynamic Images on an BUTTON CLICK :

for (int i = 0; i < c; i++) 
    {

    Image[i] = new TImage(this); 
    Image[i]->Parent = BoardItem ; // BoardItem is an Item of an TabControl    
    Image[i]->Height = 20 ;        
    Image[i]->Width = 20 ;        
    Image[i]->Position->X = d ;   // d and e are defined in the public var's.
    Image[i]->Position->Y = e ;
    Image[i]->Bitmap = Icon->Bitmap ; // Icon is an Image on my Formular
}

它的工作不错，但Icon->位图是从数据库中，这也是工作的罚款。可是，在一个第二个按钮单击旧的映像不会被删除。所以每次当我再次点击该按钮后，程序创建5个图片，但旧的仍然存在。

It's working fine but the Icon->Bitmap is from a Database , which is also working fine . But on an second Button Click the old Images are not deleted. So everytime when I'm clicking the button again, the program is creating 5 more Images but the old ones are still there.

我的问题是，现在，如何刷新旧照片？我应该删除旧的图像，然后创建新的图像？ （我想这与（删除，免费（），删除[]数组，但我总是得到一个暴力ERROR）
或者我应该刷新旧形象，万一有上的图像的位图更新的数据库，以及如何？

My question is now, how to refresh the old Images ? Should i delete the old Images an create then the new Images ? ( I tried this with ( delete , Free () , delete[] Array, but im always getting a violence ERROR ) Or should i refresh the old Images, in case there are Updates on the Bitmaps of the Images in the Database, and how ?

推荐答案

您需要两样东西：

• 请确保该指针被初始化为围绕空第一次：

• Make sure that the pointers are initialized to null the first time around:

TImage* Image[c] = {};

删除旧的图像时加载一个新的：

Delete the old image when you load a new one:

delete Image[i];
Image[i] = new TImage(this);

请注意，使用删除上一个空指针是绝对安全的;它只是没有做任何事情。所以没事就第一组图像的变化，以后每次设定自动清除了旧的，而不是漏水。

Note that using delete on a null pointer is perfectly safe; it just doesn't do anything. So nothing changes on the first set of images, and each subsequent set automatically clears out the old ones instead of leaking.

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