How to sort an NSMutableArray containing numbers as strings, in descending order

问题

I was sorting an NSMutableArray containing numbers as strings, in descending order. My array is in the same form as below:

{273,0,0,0,0,0,48,48,59,254}

I was looking for sorting it in descending order. That is expected result is:

{273,254,59,48,48,0,0,0,0,0}

I tried:

[[[myArray sortedArrayUsingSelector:@selector(compare:)] reverseObjectEnumerator] 
                                                                      allObjects];

The result was weird. It was:

{59,48,48,273,254,0,0,0,0,0} -- zeros are not getting sorted, and not proper sort

Then I tried:

[myArray sortedArrayUsingSelector: @selector(compare:)];

Again wrong output (as below):

{0,0,0,0,0,254,273,48,48,59} -- zeros came first !!! and 273 in wrong position!!!

And I also tried:

NSSortDescriptor *sortDescriptor = [[NSSortDescriptor alloc] 
                                       initWithKey:@"length" ascending:YES];
NSArray *sortDescriptors = [NSArray arrayWithObject:sortDescriptor];
[myArray sortUsingDescriptors:sortDescriptors];

Again... Result is as below:

{0,0,0,0,0,48,48,59,273,254} -- 273 in wrong position

I am totally confused. Do I need to check for those zeros? then whats happening with that 273? Am I wrong anywhere? Is there is any proper solution for me? Please help me finding out the issue.

回答1:

Try this. This may help:

NSMutableArray *myArray = ....... Your mutable array

NSArray *sorted_Array = [myArray sortedArrayUsingDescriptors:
                            @[[NSSortDescriptor sortDescriptorWithKey:@"intValue"
                                                            ascending:NO]]];

Keep Coding............ :)

来源：https://stackoverflow.com/questions/25343140/how-to-sort-an-nsmutablearray-containing-numbers-as-strings-in-descending-order