Objective-C中NSArray類的解讀

Objective-C中NSArray類的解讀

    NSArray數組類是Objective-C語言中經常使用的也是重要的一個類，除了開發中經常使用到的一些基礎功能，NSArray及其相關類中還封裝了許多更增強大的功能。有機會總結了一下，與須要的朋友們分享。

NSArray中屬性與方法：

//獲取數組中元素個數
@property (readonly) NSUInteger count;
//經過下標獲數組中的元素
- (ObjectType)objectAtIndex:(NSUInteger)index;
//初始化方法
- (instancetype)init;
//經過C語言風格的數組建立NSArray對象 須要注意，C數組中須要爲Objective對象，cnt參數爲C數組的長度
//若是cnt的值小於C數組的長度，則會對C數據進行截取賦值，若是大於則程序會崩潰
- (instancetype)initWithObjects:(const ObjectType [])objects count:(NSUInteger)cnt;
//數組的歸檔方法
- (nullable instancetype)initWithCoder:(NSCoder *)aDecoder;
//像數組中追加一個元素 這個方法會返回一個新的數組
- (NSArray<ObjectType> *)arrayByAddingObject:(ObjectType)anObject;
//像數組中追加一組元素 這個方法會返回一個新的數組
- (NSArray<ObjectType> *)arrayByAddingObjectsFromArray:(NSArray<ObjectType> *)otherArray;
//返回一個字符串，將數組中的元素以separator爲分隔符進行組合
/*
NSArray  * array = @[@1,@2,@3,@4];
將打印1,2,3,4
NSString * res = [array componentsJoinedByString:@","];
*/
- (NSString *)componentsJoinedByString:(NSString *)separator;
//判斷數組中是否包含某個元素
- (BOOL)containsObject:(ObjectType)anObject;
//數組的打印方法
@property (readonly, copy) NSString *description;
- (NSString *)descriptionWithLocale:(nullable id)locale;
- (NSString *)descriptionWithLocale:(nullable id)locale indent:(NSUInteger)level;
//獲取第一個包含於另外一個數組中的元素
- (nullable ObjectType)firstObjectCommonWithArray:(NSArray<ObjectType> *)otherArray;
//將數組中必定範圍的元素讀取到一個C數組中 objects參數須要爲分配好空間的C指針
- (void)getObjects:(ObjectType __unsafe_unretained [])objects range:(NSRange)range;
//獲取某個元素在數值中的下標值
- (NSUInteger)indexOfObject:(ObjectType)anObject;
//獲取某個範圍內的元素的下標值
- (NSUInteger)indexOfObject:(ObjectType)anObject inRange:(NSRange)range;
//獲取與給定元素相同的元素在數組中的最小下標值
- (NSUInteger)indexOfObjectIdenticalTo:(ObjectType)anObject;
//在必定範圍內 獲取與給定元素相同的元素在數組中的最小下標值
- (NSUInteger)indexOfObjectIdenticalTo:(ObjectType)anObject inRange:(NSRange)range;
//判斷兩個數組是否相同
- (BOOL)isEqualToArray:(NSArray<ObjectType> *)otherArray;
//獲取數組中第一個元素
@property (nullable, nonatomic, readonly) ObjectType firstObject NS_AVAILABLE(10_6, 4_0);
//獲取數組中最後一個元素
@property (nullable, nonatomic, readonly) ObjectType lastObject;
//獲取數組的枚舉對象
- (NSEnumerator<ObjectType> *)objectEnumerator;
//獲取數組的逆向枚舉對象
- (NSEnumerator<ObjectType> *)reverseObjectEnumerator;
/*
這個屬性能夠獲取一個已經排序數組的排序規則 在使用
- (NSArray<ObjectType> *)sortedArrayUsingFunction:(NSInteger (*)(ObjectType, ObjectType, void * __nullable))comparator context:(nullable void *)context hint:(nullable NSData *)hint;
方法時能夠將此排序規則傳入 
對於沒有排序過的數組，使用
- (NSArray<ObjectType> *)sortedArrayUsingFunction:(NSInteger (*)(ObjectType, ObjectType, void * __nullable))comparator context:(nullable void *)context;
方法會自動產生一個這樣的排序規則
*/
@property (readonly, copy) NSData *sortedArrayHint;
//經過C排序函數進行排序
/*
示例：
NSInteger sort(id obj1, id obj2, void *context){
    NSNumber *str1 =(NSNumber*) obj1;
    NSNumber *str2 =(NSNumber*) obj2;
    if ([str1 intValue] < [str2 intValue]) {
        return NSOrderedDescending;
    }
    else if([str1 intValue] == [str2 intValue])
    {
        return NSOrderedSame;
    }
    return NSOrderedAscending;
}
- (void)viewDidLoad {
    [super viewDidLoad];
    NSArray  * array = @[@1,@3,@2,@4];
    array = [array sortedArrayUsingFunction:sort context:nil];
    NSString * res = [array componentsJoinedByString:@","];
    NSLog(@"%@",res);
}
*/
- (NSArray<ObjectType> *)sortedArrayUsingFunction:(NSInteger (*)(ObjectType, ObjectType, void * __nullable))comparator context:(nullable void *)context;
//經過C排序函數進行數組排序
- (NSArray<ObjectType> *)sortedArrayUsingFunction:(NSInteger (*)(ObjectType, ObjectType, void * __nullable))comparator context:(nullable void *)context hint:(nullable NSData *)hint;
//使用函數選擇器進行數組排序
- (NSArray<ObjectType> *)sortedArrayUsingSelector:(SEL)comparator;
//獲取數組必定範圍的子數組
- (NSArray<ObjectType> *)subarrayWithRange:(NSRange)range;
//將數組寫入文件
- (BOOL)writeToFile:(NSString *)path atomically:(BOOL)useAuxiliaryFile;
//將數組寫入指定url路徑
- (BOOL)writeToURL:(NSURL *)url atomically:(BOOL)atomically;
//是數組中的全部元素調用某個方法選擇器
- (void)makeObjectsPerformSelector:(SEL)aSelector;
//功能同上 支持傳參
- (void)makeObjectsPerformSelector:(SEL)aSelector withObject:(nullable id)argument;
//獲取一個下標集合所對應的元素
- (NSArray<ObjectType> *)objectsAtIndexes:(NSIndexSet *)indexes;
//數組的下標方法 子類重寫
- (ObjectType)objectAtIndexedSubscript:(NSUInteger)idx NS_AVAILABLE(10_8, 6_0);
//對數組中的元素進行枚舉遍歷
- (void)enumerateObjectsUsingBlock:(void (^)(ObjectType obj, NSUInteger idx, BOOL *stop))block NS_AVAILABLE(10_6, 4_0);
//對數組中的元素進行枚舉遍歷
/*
typedef NS_OPTIONS(NSUInteger, NSEnumerationOptions) {
    NSEnumerationConcurrent = (1UL << 0),//正向枚舉
    NSEnumerationReverse = (1UL << 1),   //逆向枚舉
}; 
*/
- (void)enumerateObjectsWithOptions:(NSEnumerationOptions)opts usingBlock:(void (^)(ObjectType obj, NSUInteger idx, BOOL *stop))block NS_AVAILABLE(10_6, 4_0);
//在一個下標集合中枚舉
- (void)enumerateObjectsAtIndexes:(NSIndexSet *)s options:(NSEnumerationOptions)opts usingBlock:(void (^)(ObjectType obj, NSUInteger idx, BOOL *stop))block NS_AVAILABLE(10_6, 4_0);
//經過遍歷的方式查找符合條件的元素下標
- (NSUInteger)indexOfObjectPassingTest:(BOOL (^)(ObjectType obj, NSUInteger idx, BOOL *stop))predicate NS_AVAILABLE(10_6, 4_0);
//一般 能夠設置遍歷方式
- (NSUInteger)indexOfObjectWithOptions:(NSEnumerationOptions)opts passingTest:(BOOL (^)(ObjectType obj, NSUInteger idx, BOOL *stop))predicate NS_AVAILABLE(10_6, 4_0);
//同上 在必定下標集合中遍歷
- (NSUInteger)indexOfObjectAtIndexes:(NSIndexSet *)s options:(NSEnumerationOptions)opts passingTest:(BOOL (^)(ObjectType obj, NSUInteger idx, BOOL *stop))predicate NS_AVAILABLE(10_6, 4_0);
//經過遍歷的方式查找全部符合條件的元素下標
- (NSIndexSet *)indexesOfObjectsPassingTest:(BOOL (^)(ObjectType obj, NSUInteger idx, BOOL *stop))predicate NS_AVAILABLE(10_6, 4_0);
//同上
- (NSIndexSet *)indexesOfObjectsWithOptions:(NSEnumerationOptions)opts passingTest:(BOOL (^)(ObjectType obj, NSUInteger idx, BOOL *stop))predicate NS_AVAILABLE(10_6, 4_0);
//同上
- (NSIndexSet *)indexesOfObjectsAtIndexes:(NSIndexSet *)s options:(NSEnumerationOptions)opts passingTest:(BOOL (^)(ObjectType obj, NSUInteger idx, BOOL *stop))predicate NS_AVAILABLE(10_6, 4_0);
//經過block進行數組排序
- (NSArray<ObjectType> *)sortedArrayUsingComparator:(NSComparator)cmptr NS_AVAILABLE(10_6, 4_0);
//同上
/*
typedef NS_OPTIONS(NSUInteger, NSSortOptions) {
    NSSortConcurrent = (1UL << 0),//同步排序
    NSSortStable = (1UL << 4),//穩定排序
};

*/
- (NSArray<ObjectType> *)sortedArrayWithOptions:(NSSortOptions)opts usingComparator:(NSComparator)cmptr NS_AVAILABLE(10_6, 4_0);
//二分查找的枚舉參數
typedef NS_OPTIONS(NSUInteger, NSBinarySearchingOptions) {
	NSBinarySearchingFirstEqual = (1UL << 8),
	NSBinarySearchingLastEqual = (1UL << 9),
	NSBinarySearchingInsertionIndex = (1UL << 10),
};
//對區域排序的數組進行二分查找
- (NSUInteger)indexOfObject:(ObjectType)obj inSortedRange:(NSRange)r options:(NSBinarySearchingOptions)opts usingComparator:(NSComparator)cmp NS_AVAILABLE(10_6, 4_0); // binary search

//建立對象
+ (instancetype)array;
//經過一個元素建立數組對象
+ (instancetype)arrayWithObject:(ObjectType)anObject;
//經過C數組建立數組對象
+ (instancetype)arrayWithObjects:(const ObjectType [])objects count:(NSUInteger)cnt;
//經過一組元素建立數組對象
+ (instancetype)arrayWithObjects:(ObjectType)firstObj, ... NS_REQUIRES_NIL_TERMINATION;
//經過另外一個數組建立數組對象
+ (instancetype)arrayWithArray:(NSArray<ObjectType> *)array;
//初始化方法
- (instancetype)initWithObjects:(ObjectType)firstObj, ... NS_REQUIRES_NIL_TERMINATION;
- (instancetype)initWithArray:(NSArray<ObjectType> *)array;
- (instancetype)initWithArray:(NSArray<ObjectType> *)array copyItems:(BOOL)flag;
//經過文件建立數組
+ (nullable NSArray<ObjectType> *)arrayWithContentsOfFile:(NSString *)path;
//經過url建立數組
+ (nullable NSArray<ObjectType> *)arrayWithContentsOfURL:(NSURL *)url;
同上
- (nullable NSArray<ObjectType> *)initWithContentsOfFile:(NSString *)path;
- (nullable NSArray<ObjectType> *)initWithContentsOfURL:(NSURL *)url;
//獲取數組全部元素 須要傳入分配了內存的C指針
- (void)getObjects:(ObjectType __unsafe_unretained [])objects;

NSMutableArray中屬性與方法：

//向數組中追加一個元素
- (void)addObject:(ObjectType)anObject;
//向數組某個位置插入一個元素
- (void)insertObject:(ObjectType)anObject atIndex:(NSUInteger)index;
//刪除數組中最後一個元素
- (void)removeLastObject;
//刪除數組中指定位置的元素
- (void)removeObjectAtIndex:(NSUInteger)index;
//替換數組中一個位置的元素
- (void)replaceObjectAtIndex:(NSUInteger)index withObject:(ObjectType)anObject;
//初始化
- (instancetype)init NS_DESIGNATED_INITIALIZER;
- (instancetype)initWithCapacity:(NSUInteger)numItems NS_DESIGNATED_INITIALIZER;
- (nullable instancetype)initWithCoder:(NSCoder *)aDecoder NS_DESIGNATED_INITIALIZER;

//經過數組來追加元素
- (void)addObjectsFromArray:(NSArray<ObjectType> *)otherArray;
//交換兩個元素
- (void)exchangeObjectAtIndex:(NSUInteger)idx1 withObjectAtIndex:(NSUInteger)idx2;
//刪除全部元素
- (void)removeAllObjects;
//在必定範圍內刪除元素
- (void)removeObject:(ObjectType)anObject inRange:(NSRange)range;
//刪除一個元素
- (void)removeObject:(ObjectType)anObject;
//刪除指定範圍內下標最小的某個元素
- (void)removeObjectIdenticalTo:(ObjectType)anObject inRange:(NSRange)range;
//刪除某個元素 下標最小的
- (void)removeObjectIdenticalTo:(ObjectType)anObject;
//刪除必定範圍內的全部元素
- (void)removeObjectsFromIndices:(NSUInteger *)indices numIndices:(NSUInteger)cnt NS_DEPRECATED(10_0, 10_6, 2_0, 4_0);
//經過數組刪除元素
- (void)removeObjectsInArray:(NSArray<ObjectType> *)otherArray;
//經過範圍刪除元素
- (void)removeObjectsInRange:(NSRange)range;
//替換一組元素
- (void)replaceObjectsInRange:(NSRange)range withObjectsFromArray:(NSArray<ObjectType> *)otherArray range:(NSRange)otherRange;
//替換一組元素
- (void)replaceObjectsInRange:(NSRange)range withObjectsFromArray:(NSArray<ObjectType> *)otherArray;
//設置數組元素
- (void)setArray:(NSArray<ObjectType> *)otherArray;
//進行數組排序
- (void)sortUsingFunction:(NSInteger (*)(ObjectType,  ObjectType, void * __nullable))compare context:(nullable void *)context;
//進行數組排序
- (void)sortUsingSelector:(SEL)comparator;
//插入一組元素
- (void)insertObjects:(NSArray<ObjectType> *)objects atIndexes:(NSIndexSet *)indexes;
//刪除一組元素
- (void)removeObjectsAtIndexes:(NSIndexSet *)indexes;
//替換一組元素
- (void)replaceObjectsAtIndexes:(NSIndexSet *)indexes withObjects:(NSArray<ObjectType> *)objects;
//設置某個下標對應的元素 子類覆寫
- (void)setObject:(ObjectType)obj atIndexedSubscript:(NSUInteger)idx NS_AVAILABLE(10_8, 6_0);
//進行數組排序
- (void)sortUsingComparator:(NSComparator)cmptr NS_AVAILABLE(10_6, 4_0);
//進行數組排序
- (void)sortWithOptions:(NSSortOptions)opts usingComparator:(NSComparator)cmptr NS_AVAILABLE(10_6, 4_0);

//建立數組 numItems爲元素個數
+ (instancetype)arrayWithCapacity:(NSUInteger)numItems;
//經過文件建立數組
+ (nullable NSMutableArray<ObjectType> *)arrayWithContentsOfFile:(NSString *)path;
//經過url建立數組
+ (nullable NSMutableArray<ObjectType> *)arrayWithContentsOfURL:(NSURL *)url;
同上
- (nullable NSMutableArray<ObjectType> *)initWithContentsOfFile:(NSString *)path;
- (nullable NSMutableArray<ObjectType> *)initWithContentsOfURL:(NSURL *)url;

 

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