1         //字典的創建 2         NSDictionary *d1 = [NSDictionary dictionary]; 3         //將創建的字典的內容設置為制定的文件的內容 4         NSString *path = @"";//文件路徑 5         NSDictionary *d2 = [NSDictionary dictionaryWithContentsOfFile:path]; 6         //創建具有一個鍵值的字典 7         NSDictionary *d3 = [NSDictionary dictionaryWithObject:@"s" forKey:@"s"]; 8         //創建具有多個鍵值的字典  鍵值對必需對應 9         //值在前  鍵在后10         NSDictionary *d4 = [NSDictionary dictionaryWithObjectsAndKeys:@"ss",@"2",11                                          @"ss",@"1",12                                          nil];13         14         //利用數組創建字典15         NSArray *key = @[@"2",@"3",@"4"];16         NSArray *obj = @[@"ss",@"ff",@"gg"];17         NSDictionary *d5 = [NSDictionary dictionaryWithObjects:obj forKeys:key];18         //便捷方式19         //鍵在前 值在后20         NSDictionary *d6 = @{21                              @"2":@"d",22                              @"3":@"d"};23         24         //init初始化25         //將初始化的字典內容設置為指定文件內容26         NSDictionary *dd = [[NSDictionary alloc]initWithContentsOfFile:path];27         //初始化具有多個鍵-值的字典(利用數組)28         NSDictionary *dd1 = [[NSDictionary alloc]initWithObjects:obj forKeys:key];29         //初始化具有多個鍵-值的字典30         NSDictionary *dd2 = [[NSDictionary alloc]initWithObjectsAndKeys:31         @"ss",@"2",32         @"ss",@"1", nil];33         34         35         36         //字典基本操作37         //字典是無序的  鍵不可以重復 值可以重復38         //返回所有鍵39         NSLog(@"%@",[dd2 allKeys]);40         //返回所有值41         NSLog(@"%@",[dd2 allValues]);42         //返回所有值對應的鍵43         NSLog(@"%@",[dd2 allKeysForObject:@"ss"]);44         //返回對應鍵的值  最常見 最重要45         NSLog(@"%@",[dd2 objectForKey:@"ss"]);46         //鍵值對47         NSLog(@"%zi",dd2.count);48 49         50         //不可變字典51         //創建52         NSMutableDictionary *dic = [NSMutableDictionary dictionary];53         //分配空間54         NSMutableDictionary *dic1 = [[NSMutableDictionary alloc]initWithCapacity:10];55         //創建并賦值56         NSMutableDictionary *dic2 = [NSMutableDictionary dictionaryWithObjectsAndKeys:@"ss",@"2",57                                      @"ss",@"1", nil];58         //添加鍵值對59         [dic2 setObject:@"s" forKey:@"sdads"];60         //刪除所有鍵值對61         [dic2 removeAllObjects];62         //刪除指定鍵對應的鍵值對63         [dic2 removeObjectForKey:@"sd"];64         65         66         //字典的遍歷67         //快速遍歷68         for (id key in dic2) {69             NSLog(@"%@ = %@",key,[dic2 objectForKey:key]);70         }71         //代碼塊遍歷72         [dic2 enumerateKeysAndObjectsUsingBlock:^(id key, id obj, BOOL *stop) {73             NSLog(@"%@ %@",key,obj);74         }];75         //迭代器遍歷76         //可以輸出鍵和值77         NSEnumerator *en = [dic2 keyEnumerator];//將所有鍵裝入數組78         id key2 = nil;79         while (key2 = [en nextObject]) {80             NSLog(@"%@ %@",key2,[dic2 objectForKey:key2]);81         }82         NSEnumerator *en1 = [dic2 objectEnumerator];//將所有值裝入數組83         //只可以輸出值84         id obj3 = nil;85         while (obj3 = [en1 nextObject]) {86             NSLog(@"%@", obj);87         }88         89         90         //鍵給空值會異常   值給控制就是結束標志