如何使用另一个NSArray的最后30个对象创建一个新的NSArray？

Question

I have a NSArray with 493 objects and need to create a new one with just the last 30 objects from the first array.

I know how to create a new array with the first 10 or 30 etc, but the other way around I can't.

I tried using this code:

NSArray *tempArray = [qtdPrecos subarrayWithRange:NSMakeRange([qtdPrecos count]-30, [qtdPrecos count]-1)];

But I got this error:

[NSArray subarrayWithRange:]: range {463, 492} extends beyond bounds [0 .. 492]'

So any one could help??? Thanks!!!

Answer 1

NSRange结构的第二部分是长度

Answer 2

在NSMakeRange中，第一个参数是开始，但第二个参数是范围的长度 。