' [blah addObject:@ " 1 "; ' and ' [blah insertObject:@ " 0 " atIndex:0]; '之间的区别是什么?

What is the difference between:

的区别是什么:

[blah addObject:@"1"];

And

和

[blah insertObject:@"0" atIndex:0];

???

? ? ?

I know they're both for a NSMutableArray.

我知道他们都是为了NSMutableArray。

1 个解决方案

#1

addObject adds an object at last. insertObject:atIndex adds an object at specified index. All objects further to that specified index are shifted one position right.

addObject最后添加一个对象。atIndex在指定的索引处添加一个对象。在指定索引后面的所有对象都被右移一个位置。

For example, say you have an array with following objects:

例如，假设您有一个具有以下对象的数组:

A B C D

And you add E using addObject. Then it will look like:

用addObject添加E。然后它会看起来像:

A B C D E

Then you insert F at index 2. Then it will look like:

然后在索引2处插入F。然后它会看起来像:

A B F C D E

#1