NSArray *ary = @[@"a3",@"a1",@"a2",@"a10",@"a24"];NSLog(@"%@",ary);NSArray *myary = [ary sortedArrayUsingComparator:^(NSString * obj1, NSString * obj2){    return (NSComparisonResult)[obj1 compare:obj2 options:NSNumericSearch];}];NSLog(@"%@",myary);结果 ( a3,a1, a2, a10, a24 ) ( a1, a2,a3, a10, a24 )

 方法2

NSArray *ary = @[@"a3",@"a1",@"a2",@"a24",@"a14"];NSLog(@"%@",ary);NSSortDescriptor *sd1 = [NSSortDescriptor sortDescriptorWithKey:nil ascending:NO];//yes升序排列，no,降序排列NSArray *myary = [ary sortedArrayUsingDescriptors:[NSArray arrayWithObjects:sd1, nil]];//注意这里的ary进行排序后会生产一个新的数组指针，myary，不能在用ary,ary还是保持不变的。NSLog(@"%@",myary);//    (a3, a1, a2,a24,a14)//    (a3, a24, a2, a14, a1)

 方法3

[ary sortedArrayUsingSelector:@selector(compare:)];//这个是一直默认升序