oc 字典应用实例-成绩科目排序

 1  NSMutableArray *mutArray1 = [[NSMutableArray alloc]init];
 2         NSDictionary *dic = [[NSDictionary alloc]initWithObjectsAndKeys:[NSNumber numberWithInt:98],@"chinese", [NSNumber numberWithInt:68],@"math",[NSNumber numberWithInt:108],@"english",[NSNumber numberWithInt:58],@"politics",nil];
 3         NSArray *array = [dic allValues];
 4         NSLog(@"%@",array);
 5         array = [array sortedArrayUsingSelector:@selector(compare:)];
 6         NSLog(@"%@",array);
 7 //        NSArray *array1 = [dic allKeysForObject:[NSNumber numberWithInt:98]];
 8 //        NSString *str2 = [array1 objectAtIndex:0];
 9 //        NSLog(@"%@",str2);
10         for (int i = 0; i < array.count; i ++)
11         {
12             NSArray *array2 = [dic allKeysForObject:[array objectAtIndex:i]];//在排好序数组中按照值取键
13             NSString *str2 = [array2 objectAtIndex:0];//在数组中把键取出
14             [mutArray1 addObject:str2];//取出的键加到新的数组中
15         }
16         NSLog(@"mutArray2 = %@",mutArray1);
17     }