NSArray 添加元素 [英] NSArray adding elements

问题描述

我必须创建一个动态的 NSArray，也就是说，我不知道数组的大小或数组将包含哪些元素.元素需要动态添加到数组中.我查看了 NSArray 类参考.有一个方法叫做arrayWithObjects，应该在初始化数组本身的时候使用.但我不知道如何实现我需要做的事情.

I have to create a dynamic NSArray, that is, I don't know the size of the array or what elements the array is going to have. The elements need to be added to the array dynamically. I looked at the NSArray class reference. There is a method called arrayWithObjects, which should be used at the time of initializing the array itself. But I don't know how to achieve what I need to do.

我需要做一些如下的事情:

I need to do some thing like the following:

NSArray *stringArray = [[NSArray init] alloc] ;  
for (int i = 0; i < data.size; i++){  
    stringArray.at(i) = getData(i);
}

推荐答案

如果您创建一个 NSArray，您将无法向其中添加元素，因为它是不可变的.您应该尝试使用 NSMutableArray 代替.

If you create an NSArray you won't be able to add elements to it, since it's immutable. You should try using NSMutableArray instead.

此外，您颠倒了 alloc 和 init 的顺序.alloc 创建一个实例，init 初始化它.

Also, you inverted the order of alloc and init. alloc creates an instance and init initializes it.

代码看起来像这样(假设 getData 是一个全局函数):

The code would look something like this (assuming getData is a global function):

NSMutableArray *stringArray = [[NSMutableArray alloc] init];
for(int i=0; i< data.size; i++){
   [stringArray addObject:getData(i)];
}

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