NSDictionary全部API的学习。

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@property (readonly)NSUInteger count;

//1.利用指定的key寻找对应的value

- (id)objectForKey:(id)aKey;

//2. keyEnumerator得到一个字典的所有键值

- (NSEnumerator *)keyEnumerator;

//3.初始化字典

- (instancetype)initNS_DESIGNATED_INITIALIZER;

//4.条件编译根据不同情况来初始化字典

#if TARGET_OS_WIN32

- (instancetype)initWithObjects:(constid [])objects forKeys:(constid [])keys count:(NSUInteger)cnt;

#else

- (instancetype)initWithObjects:(constid [])objects forKeys:(constid <NSCopying> [])keys count:(NSUInteger)cntNS_DESIGNATED_INITIALIZER;

#endif

- (instancetype)initWithCoder:(NSCoder *)aDecoderNS_DESIGNATED_INITIALIZER;

@end

@interface NSDictionary (NSExtendedDictionary)

//5.数组所有key属性

@property (readonly,copy)NSArray *allKeys;

//6.根据所填入的object返回对应所有的key键值

- (NSArray *)allKeysForObject:(id)anObject;

//7.属性 字典所有value  

@property (readonly,copy)NSArray *allValues;

//8.属性 字符串描述

@property (readonly,copy)NSString *description;

//9.属性 字符串描述文件格式

@property (readonly,copy)NSString *descriptionInStringsFileFormat;

//10.根据设置的locale进行连接数组

- (NSString *)descriptionWithLocale:(id)locale;

//11.根据设置的locale进行连接数组

- (NSString *)descriptionWithLocale:(id)locale indent:(NSUInteger)level;

//12.判断字典是否相等

- (BOOL)isEqualToDictionary:(NSDictionary *)otherDictionary;

//13.得到一个字典的所有values

- (NSEnumerator *)objectEnumerator;

//14.字典将某个特定的数组作为key值传进去得到对应的value，如果某个key找不到对应的key，就用notFoundMarker提前设定的值代替

- (NSArray *)objectsForKeys:(NSArray *)keys notFoundMarker:(id)marker;

    //NSDictionary *dic=[NSDictionarydictionaryWithObjectsAndKeys:@"K1",@"V1",@"K2",@"V2",@"K3",@"V3",nil];

    //NSArray *arr1=[NSArrayarrayWithObjects:@"V1",@"V2",@"VG",nil];

    //NSArray *ARR= [dicobjectsForKeys:arr1notFoundMarker:@"BB"];

    //NSLog(@"测试测试%@",ARR);

    //打印：

    //2015-06-08 11:30:54.139 NSDictionary[1624:64989]测试测试(

   //K1,

   //BB,

   //BB

    //)

//15.将字典写进特定的路径path

- (BOOL)writeToFile:(NSString *)path atomically:(BOOL)useAuxiliaryFile;

- (BOOL)writeToURL:(NSURL *)url atomically:(BOOL)atomically;// the atomically flag is ignored if url of a type that cannot be written atomically.

//16.字典按照value的大小顺序来对keys键值进行排序（通过value排序，返回key集合）

- (NSArray *)keysSortedByValueUsingSelector:(SEL)comparator;

//NSDictionary *dic1=[NSDictionarydictionaryWithObjectsAndKeys:@"4",@"A",@"6",@"C",@"5",@"B",nil];

    //NSArray *arr2= [dic1keysSortedByValueUsingSelector:@selector(compare:)];

    //NSLog(@"奇葩奇葩%@",arr2);

//2015-06-08 14:41:59.152 NSDictionary[2749:117502]奇葩奇葩(

   //A,

   //B,

   //C

//)

//17.

- (void)getObjects:(id__unsafe_unretained [])objects andKeys:(id__unsafe_unretained [])keys;

//18.

- (id)objectForKeyedSubscript:(id)keyNS_AVAILABLE(10_8,6_0);

//19.利用block对字典进行遍历

- (void)enumerateKeysAndObjectsUsingBlock:(void (^)(id key,id obj, BOOL *stop))blockNS_AVAILABLE(10_6,4_0);

//例子:

    NSDictionary *dic = [NSDictionarydictionaryWithObjects:@[@"1",@"2",@"3"]forKeys:@[@"one",@"two",@"three"]];

   NSString *stopKey =@"two";

   __blockBOOL stopEarly =NO;

    [dicenumerateKeysAndObjectsUsingBlock:^(id key,id obj,BOOL *stop) {

       NSLog(@"%@,%@",key,obj);

        //访问对象类型变量

       if ([keyisEqualToString:stopKey]) {

            *stop =YES;

            //访问__block表识的局部类型变量

            stopEarly =YES;

           //直接访问属性

            NSLog(@"self.name = tom");

            ;

        }

    }];

//输出:

2015-06-08 15:19:09.608 NSDictionary[3035:136164] one,1

2015-06-08 15:19:09.609 NSDictionary[3035:136164] two,2

2015-06-08 15:19:09.609 NSDictionary[3035:136164] self.name = tom

//20.同上一样利用block对字典进行遍历，不过加了排序的顺序选项options正反序

- (void)enumerateKeysAndObjectsWithOptions:(NSEnumerationOptions)opts usingBlock:(void (^)(id key, id obj,BOOL *stop))blockNS_AVAILABLE(10_6,4_0);

//21.和第16一样都是利用value对keys进行排序，只不过这个加上了一个可设定的NSComparato参数条件来比较

- (NSArray *)keysSortedByValueUsingComparator:(NSComparator)cmptrNS_AVAILABLE(10_6,4_0);

//例子

   NSArray *sortedKeys = [dickeysSortedByValueUsingComparator:^NSComparisonResult(id obj1,id obj2) {

       if ([obj1integerValue] > [obj2integerValue]) {

            return (NSComparisonResult)NSOrderedAscending;

        }

       if ([obj1integerValue] < [obj2integerValue]) {

            return (NSComparisonResult)NSOrderedDescending;

        }

        return (NSComparisonResult)NSOrderedSame;

    }];

    NSLog(@"利用keysSortedByValueUsingComparator进行排序%@",sortedKeys);

//输出:

2015-06-08 16:07:12.361 NSDictionary[3420:160942]利用keysSortedByValueUsingComparator进行排序(

    one,

    three,

    two

)

//22.通过values对字典的keys进行排序，可以有排序的选择，还可添加设定的NSComparato参数条件来比较

- (NSArray *)keysSortedByValueWithOptions:(NSSortOptions)opts usingComparator:(NSComparator)cmptrNS_AVAILABLE(10_6,4_0);

//23.这是一个很好的对字典进行过滤的方法,返回keys的集合，这些keys符合参数block的约束，在block内部在特定的条件下返回yes，返回的这个集合会保留当前遍历到那个字典对象的信息

- (NSSet *)keysOfEntriesPassingTest:(BOOL (^)(id key,id obj, BOOL *stop))predicateNS_AVAILABLE(10_6,4_0);

//例子:

NSDictionary * numsDic =@{@(2):@"second",@(4):@"first",@(1):@"thrid"};

   NSSet * filteredKeys = [numsDickeysOfEntriesPassingTest:^BOOL(id key,id obj,BOOL *stop) {

       BOOL result =NO;

       NSNumber * numKey = key;

       if (numKey.integerValue >2) {

            result =YES;

        }

       returnYES;

    }];

    NSLog(@"filteredKeys.description----%@",filteredKeys.description);

//打印:

2015-06-08 17:34:37.741 NSDictionary[4085:193311] filteredKeys.description----{(

    4

)}

//23.用法同上，增加了一个列举的选项选择

- (NSSet *)keysOfEntriesWithOptions:(NSEnumerationOptions)opts passingTest:(BOOL (^)(id key, id obj,BOOL *stop))predicateNS_AVAILABLE(10_6,4_0);

@end

@interface NSDictionary (NSDictionaryCreation)

//24.快速创建一个空字典

+ (instancetype)dictionary;

//25.快速创建字典并且赋初值

+ (instancetype)dictionaryWithObject:(id)object forKey:(id <NSCopying>)key;

//26.条件编译 不同情况创建字典的几种方法

#if TARGET_OS_WIN32

+ (instancetype)dictionaryWithObjects:(constid [])objects forKeys:(constid [])keys count:(NSUInteger)cnt;

#else

+ (instancetype)dictionaryWithObjects:(constid [])objects forKeys:(constid <NSCopying> [])keys count:(NSUInteger)cnt;

#endif

+ (instancetype)dictionaryWithObjectsAndKeys:(id)firstObject, ...NS_REQUIRES_NIL_TERMINATION;

//27.创建新字典 赋值一个字典

+ (instancetype)dictionaryWithDictionary:(NSDictionary *)dict;

//28.创建字典，通过数组赋值values和keys

+ (instancetype)dictionaryWithObjects:(NSArray *)objects forKeys:(NSArray *)keys;

//29.使用指定的以nil为结尾的对象与键对列表初始化列表

- (instancetype)initWithObjectsAndKeys:(id)firstObject, ...NS_REQUIRES_NIL_TERMINATION;

//30.使用另一个字典初始化字典

- (instancetype)initWithDictionary:(NSDictionary *)otherDictionary;

//31.使用另一个字典初始化字典，还可以为每个对象创建新的副本

- (instancetype)initWithDictionary:(NSDictionary *)otherDictionary copyItems:(BOOL)flag;

//32.使用指定的对象与键初始化字典

- (instancetype)initWithObjects:(NSArray *)objects forKeys:(NSArray *)keys;

//33.使用本地文件的内容初始化字典

+ (NSDictionary *)dictionaryWithContentsOfFile:(NSString *)path;

//34.使用URL的内容初始化字典

+ (NSDictionary *)dictionaryWithContentsOfURL:(NSURL *)url;

//35.使用本地文件的内容初始化字典

- (NSDictionary *)initWithContentsOfFile:(NSString *)path;

//36.使用URL的内容初始化字典

- (NSDictionary *)initWithContentsOfURL:(NSURL *)url;

@end

/**************** Mutable Dictionary****************/

@interface NSMutableDictionary :NSDictionary

//37.根据对应的key删除对应的value以及自身的key，

- (void)removeObjectForKey:(id)aKey;

//38.在可变字典中，改变对应的key的value

- (void)setObject:(id)anObject forKey:(id <NSCopying>)aKey;

//39.创建字典初始化

- (instancetype)initNS_DESIGNATED_INITIALIZER;

//40.初始化字典并且指定大小

- (instancetype)initWithCapacity:(NSUInteger)numItemsNS_DESIGNATED_INITIALIZER;

//41.序列化对象

- (instancetype)initWithCoder:(NSCoder *)aDecoderNS_DESIGNATED_INITIALIZER;

@end

@interface NSMutableDictionary (NSExtendedMutableDictionary)

//42.一个字典整体拼接另一个字典的方法

- (void)addEntriesFromDictionary:(NSDictionary *)otherDictionary;

//43.删除字典所有的数据

- (void)removeAllObjects;

//44.根据指定的数据keys删除对应的values

- (void)removeObjectsForKeys:(NSArray *)keyArray;

//45.给可变字典添加一组新字典

- (void)setDictionary:(NSDictionary *)otherDictionary;

//46.以数组下标的形式来访问相应键的值

- (void)setObject:(id)obj forKeyedSubscript:(id <NSCopying>)keyNS_AVAILABLE(10_8,6_0);

@end

@interface NSMutableDictionary (NSMutableDictionaryCreation)

//47.快速创建可变字典并且初始化大小

+ (instancetype)dictionaryWithCapacity:(NSUInteger)numItems;

//48.快速创建可变字典通过指定的文件路径

+ (NSMutableDictionary *)dictionaryWithContentsOfFile:(NSString *)path;

//49.快速创建可变字典通过URL

+ (NSMutableDictionary *)dictionaryWithContentsOfURL:(NSURL *)url;

//50.使用本地文件的内容创建可变字典

- (NSMutableDictionary *)initWithContentsOfFile:(NSString *)path;

//51.使用URL的内容创建可变字典

- (NSMutableDictionary *)initWithContentsOfURL:(NSURL *)url;

@end

@interface NSDictionary (NSSharedKeySetDictionary)

//52.用来创建预订好的key集合，返回的值作为NSMutableDictionary的dictionaryWithSharesKeySet参数传入，可以重用key，从而节约copy操作，节省内存。

+ (id)sharedKeySetForKeys:(NSArray *)keysNS_AVAILABLE(10_8,6_0);

@end

@interface NSMutableDictionary (NSSharedKeySetDictionary)

//53.创建字典，共享键集会复用对象

+ (NSMutableDictionary *)dictionaryWithSharedKeySet:(id)keysetNS_AVAILABLE(10_8,6_0);

@end