在多维 NSMutableArray 中添加对象 [英] Adding objects in Multidimensional NSMutableArray

问题描述

我对如何在多维数组中添加对象感到很困惑.

I'm quite confused on how to add objects in multidimensional arrays.

初始化多维数组和简单数组一样吗?

Is initializing multidimensional arrays are the same with just a simple array?

这是我的初始化.

testList = [[NSMutableArray alloc] init];

我需要做类似的事情

testList[i][j] = item;

我试过了

[[[testList objectAtIndex:i]objectAtIndex:j] addObject:item];

但它似乎不起作用:(

推荐答案

你需要添加很多 C 来做到这一点.了解 NSMutableArray 的工作原理以及与 C/C++ 中已知的二维数组相比有何不同，这一点很重要.

You are add to much C to do this. This is important to know how to NSMutableArray works and how it's different compare to 2D arrays known from C/C++.

在可变数组中，您可以存储另一个数组.例如:

In mutable array you could store another arrays. For example:

NSMutableArray *first = [[NSMutableArray alloc] init];
NSMutableArray *second = [[NSMutableArray alloc] init];

[first addObject:second];

现在你在第一个数组的第一行有了数组！这很像 C/C++ 2D 数组.

Now you have array in first row in first array! This is something very like C/C++ 2D arrays.

因此，如果您想向 "0,0" 添加某个对象，请执行以下操作:

So if you want to add some object to "0,0" you do this:

NSString *mytest = [[NSString alloc] initWithString:@"test"];
[second addObject:mytest];
[first addObject:second];

所以现在你的 second 包含 NSStrings 而 first 包含 second.现在您可以随意循环播放.

So now your second contains NSStrings and first contains second. Now you can loop this like you want.

----如果你想要 1,0 你只需要 second NSMutableArray 的另一个实例.例如你有这个数组:

---- IF you want 1,0 you simply need another instance of second NSMutableArray. For example you have this array:

所以这里你将在 second 数组中有 3 个元素.

So here you will be have 3 elements in second array.

NSMutableArray *first = [[NSMutableArray alloc] init];
for(int i =0 ; i < your_size_condition ; i++) {//if you have size, if don't not a problem, you could use while!
   NSArray *second = [[NSArray alloc] initWithObjects:"@something",@"somethingelse",@"more",nil];
   [first addObject:second];
}

您可能想要实现 NSCopying 协议来做到这一点.

You may want to implement NSCopying protocol to do this.

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