copy NSArray inside an empty NSArray

I have a first NSArray firstArray and I do

[firstArray remo开发者_C百科veAllObjects];

after I want fill it with the content of an other array secondArray

is it right write in this way?

firstArray = secondArray; 

No, firstArray = secondArray will reassign the pointers, this is not the behavior you want. You want [firstArray addObjectsFromArray:secondArray]

Since the firstArray is an NSArray, you will want to do this instead:

firstArray = [NSArray arrayWithArray:secondArray];