NSMutableArray排序

    NSMutableArray *array = [NSMutableArray array];
    for (int i = 0; i < 10; i ++) {
        [NSThread sleepForTimeInterval:1.f];
        Test23 *test = [[Test23 alloc] init];
        test.name = [NSString stringWithFormat:@"name_%d",i];
        test.date = [NSDate date];
        [array addObject:test];
        [test release];
    }
   
    for (Test23 *test in array) {
        NSLog(@"%@",test.name);
        NSLog(@"%f",test.date.timeIntervalSince1970);
    }
   
   
    [array sortUsingComparator:^NSComparisonResult(id obj1, id obj2) {
       
        Test23 *test1 = obj1;
        Test23 *test2 = obj2;
       
        double a = test1.date.timeIntervalSince1970;
        double b = test2.date.timeIntervalSince1970;
        if (a < b) {
            return NSOrderedDescending;
        } else if (a > b) {
            return NSOrderedAscending;
        } else {
            return NSOrderedSame;
        }
    }];
   
    NSLog(@">>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>");
   
    for (Test23 *test in array) {
        NSLog(@"%@",test.name);
        NSLog(@"%f",test.date.timeIntervalSince1970);
    }