xcode 如何在objective c中使用NSArray对象的NSArray？
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How to use NSArray of NSArray object in objective c?
提问by user1306926
I declared a NSArrayobject in .h file as
我NSArray在 .h 文件中声明了一个对象
@property (nonatomic, assign) NSArray *scnArray;
and in .h file under - (void)viewDidLoadI created three different NSArrayobjects as
在 .h 文件中，- (void)viewDidLoad我创建了三个不同的NSArray对象作为
NSArray *obj1 = [[NSArray alloc] initWithObjects:@"1",@"0",@"0",nil];
NSArray *obj2 = [[NSArray alloc] initWithObjects:@"0",@"3",@"0",nil];
NSArray *obj3 = [[NSArray alloc] initWithObjects:@"0",@"0",@"5",nil];
scnArray = [[NSArray alloc] initWithArray:obj1];
[scnArray arrayByAddingObjectsFromArray:obj2];
[scnArray arrayByAddingObjectsFromArray:obj3];
and if I access this scnArray from any other function
如果我从任何其他函数访问这个 scnArray
NSArray *caseArray = [scnArray objectAtIndex:index];//index will be 0, 1, 2...
NSArray *caseArray = [scnArray objectAtIndex:index];//索引将为 0, 1, 2 ...
I am getting BAD_ACCESS_ERROR. What is the problem here and how can I correct to use it?
我得到BAD_ACCESS_ERROR. 这里有什么问题，我该如何纠正使用它？
采纳答案by Dr.Kameleon
Try this :
尝试这个 ：
NSArray *obj1 = [[NSArray alloc] initWithObjects:@"1",@"0",@"0",nil];
NSArray *obj2 = [[NSArray alloc] initWithObjects:@"0",@"3",@"0",nil];
NSArray *obj3 = [[NSArray alloc] initWithObjects:@"0",@"0",@"5",nil];
scnArray = [[NSArray alloc] initWithArray:obj1];
scnArray = [scnArray arrayByAddingObjectsFromArray:obj2];
scnArray = [scnArray arrayByAddingObjectsFromArray:obj3];
The arrayByAddingObjectsFromArray:function adds all objects from array B to array A, and return the result (=the array containing both A's and B's elements).
该arrayByAddingObjectsFromArray:函数将数组 B 中的所有对象添加到数组 A，并返回结果（=包含 A 和 B 元素的数组）。
So, you should simply GET that result... :-)
所以，你应该简单地得到那个结果...... :-)
IMPORTANT :scnArrayMUST be an NSMutableArrayarray, and NOT an NSArray(it's changing, right?); so make sure you edit that part too...
重要提示：scnArray必须是一个NSMutableArray数组，而不是一个NSArray（它正在改变，对吧？）；所以请确保您也编辑该部分...
ALSO :NSArray *caseArray = [scnArray objectAtIndex:index];- this doesn't make any sense. Setting an array to an ELEMENT of the scnArray? It doesn't contain arrays, right? It just contains ELEMENTS of those arrays (the ones we've added)...
还：NSArray *caseArray = [scnArray objectAtIndex:index];- 这没有任何意义。将数组设置为scnArray? 它不包含数组，对吗？它只包含这些数组的元素（我们添加的那些）......
回答by JeremyP
arrayByAddingObject:does not add the new object to the receiver, it creates a completely new array and returns it. You should use something like:
arrayByAddingObject:不会将新对象添加到接收器，它会创建一个全新的数组并返回它。你应该使用类似的东西：
scnArray = [[NSArray alloc] initWithObjects: obj1, obj2, obj3, nil];
Don't forget that if you are not using ARC or GC, all of these arrays will need to be released at some point.
不要忘记，如果您不使用 ARC 或 GC，所有这些数组都需要在某个时候释放。
