OC温习四：数组

/**
     arrayByAddingObject
     -- 往数组A添加一个数据，返回一个数组的形式，即必须有一个数组来接受
     */
    NSArray *array = [NSArray arrayWithObjects:@"1",@"2",@"3", nil];
    array = [array arrayByAddingObject:@"4"];
    NSLog(@"-----addarr=%@-----", array);  //>>1,2,3,4

    /**
     arrayByAddingObjectsFromArray
     -- 往数组A添加一组数组B，返回数组类型，需要一个数组来接受数据
     */
    NSArray *addArr2 = [array arrayByAddingObjectsFromArray:array];
    NSLog(@"-----addArr2=%@-----", addArr2); //>>>1,2,3,4,1,2,3,4

    /**
     componentsJoinedByString
     -- 将数据A以 需要的分隔符分割开，组成一个字符串：例如数组A= [1，2，3]；分隔符为^, 字符串为1^2^3
     */
    NSString *arrayStr = [array componentsJoinedByString:@"^"];
    NSLog(@"-----arrayStr=%@-----", arrayStr); //>>>1^2^3

    /**
     containsObject
     -- 数组是否包含某个对象
     */
    BOOL isContains = [array containsObject:@"5"];
    NSLog(@"-----isContains=%d-----", isContains);  //>>>NO

    /**
     description
     */
    NSString *arrDes = [array description];
    NSLog(@"-----description=%@-----", arrDes);

    /**
     indexOfObject
     --判断 anObject 对象是否存在数组中如果存在返回，对象所在的下标;如果不存在，返回NSNotFund
     */
    NSUInteger index = [addArr2 indexOfObject:@"5"];
    NSLog(@"-----index=%ld-----", index);

    /**
    indexOfObjectIdenticalTo: inRange:
    -- 判断 anObject 对象是否存在数组中range范围内，如果存在，返回下标了；如果不存在，返回NSNotFund
     */
    NSUInteger index2 = [addArr2 indexOfObject:@"3" inRange:NSMakeRange(1, 3)];
    NSLog(@"-----index2 = %ld-----", index2);  // 2

    /**
    objectEnumerator  --正序遍历数组
    reverseObjectEnumerator  --反序遍历数组
     */
    NSEnumerator *rator = [array objectEnumerator];
    id obj = nil;
    while (obj = [rator nextObject]) {
        NSLog(@"----obj=-%@-----",obj);
    }

    /**
    isEqualToArray
     -- 两个数组是否相等
     */
    BOOL isSame = [addArr2 isEqualToArray:array];
    NSLog(@"-----isSame = %d-----", isSame);

    /**
     sortedArrayUsingSelector
     -- 如果只是对字符串排序的话， 可以利用 字符串自带的compare：方法；也可以自己写compare：方法，进行对象的比较
     */

    /**
     subarrayWithRange
     -- 截取数组 range的数组
     */
    NSArray *subArray = [addArr2 subarrayWithRange:NSMakeRange(2, 4)];
    NSLog(@"-----subArray=%@-----", subArray);

    /**
     writeToFile: atomically:
     -- 把数据写入本地
     */

    /**
     writeToURL: atomically:
     --保存数组至一个URL
     */

    /**
     makeObjectsPerformSelector:(SEL)aSelector
     -- 让每个数组都调用 aSelector 这个方法
     */

    NSLog(@"-----addArr2=%@-----", addArr2);

    /**
     objectAtIndexedSubscript:
     -- 获取数组中 idx 索引的数据
     */
    NSString *strIndex = [addArr2 objectAtIndexedSubscript:3];
    NSLog(@"-----strIndex=%@-----", strIndex); //>>>4

    /**
    enumerateObjectsUsingBlock:
     -- 这个方法也是一种循环的方法与for，while实现的功能一样；当stop = yes的时候，就停止循环
     */
    [addArr2 enumerateObjectsUsingBlock:^(id  _Nonnull obj, NSUInteger idx, BOOL * _Nonnull stop) {
//        NSLog(@"-----obj= %@ idx = %ld -----", obj, idx);
    }];

    /**
     enumerateObjectsWithOptions:(NSEnumerationOptions)opts usingBlock:
     -- 这个方法也是一种循环的方法与for，while实现的功能一样；当stop = yes的时候，就停止循环
     */
    //NSEnumerationReverse 倒序遍历
    [array enumerateObjectsWithOptions:NSEnumerationReverse usingBlock:^(id obj, NSUInteger idx, BOOL * _Nonnull stop) {
         NSLog(@"-----obj= %@ idx = %ld -----", obj, idx);
        //当需要结束循环的时候,调用stop,赋予YES
//        if (idx ==3) {
//            *stop = YES;
//        }

    }];

    /**
    enumerateObjectsAtIndexes:(NSIndexSet *)s options:
     -- 在制定的数组范围 s 内 遍历数据
     */
    [addArr2 enumerateObjectsAtIndexes:[NSIndexSet indexSetWithIndexesInRange:NSMakeRange(2, 4)] options:NSEnumerationReverse usingBlock:^(id  _Nonnull obj, NSUInteger idx, BOOL * _Nonnull stop) {
        NSLog(@"-----obj= %@ idx = %ld -----", obj, idx);
    }];

    /**
     indexOfObjectPassingTest
     --  根据条件用来获取一个NSUIndex 对象，主要是根据条件进行数据遍历使用
     */
    NSInteger testIndex = [array indexOfObjectPassingTest:^ BOOL (id tr,NSUInteger index, BOOL *te){
        NSString *s = (NSString *)tr;
        if([@"4" isEqualToString:s])
        {
            return YES;
        }
        return NO;
    }];

    NSLog(@"index==%ld=.",testIndex);  //>>> 3

    /**
     sortedArrayUsingComparator:
     -- 排序 ， 这个方法本身就是按递增的方式排序。

     NSOrderedAscending
     -The left operand is smaller than the right operand.
     NSOrderedSame
     -The two operands are equal.
     NSOrderedDescending
     -The left operand is greater than the right operand

     */

    NSArray *numberArray = @[@"3", @"4", @"9", @"1"];  //递增
    NSArray *sortArray =  [numberArray sortedArrayUsingComparator:^NSComparisonResult(id  _Nonnull obj1, id  _Nonnull obj2) {
        if ([obj1 integerValue] > [obj2 integerValue]) {
            return NSOrderedDescending;
        }else {
            return NSOrderedAscending;
        }
    }];

    NSLog(@"-----sortArray=%@-----", sortArray);  //>>>1 3 4 9

    /**
     sortedArrayWithOptions:(NSSortOptions)opts usingComparator
     -- 与上个方法一致
     */

此外还提供了NAMutableArray的方法，这个方法常用，都知道意思，只列举方法：

@interface NSMutableArray<ObjectType> : NSArray<ObjectType>

- (void)addObject:(ObjectType)anObject;  --往数组添加数据
- (void)insertObject:(ObjectType)anObject atIndex:(NSUInteger)index;  --往数组的第index下标插入一个anobject数据
- (void)removeLastObject;  -- 移除数组的最后一个数据
- (void)removeObjectAtIndex:(NSUInteger)index;  --移除数组中第index个数据
- (void)replaceObjectAtIndex:(NSUInteger)index withObject:(ObjectType)anObject; --用 anobject 替换 数组 中 第index个数据
- (instancetype)init NS_DESIGNATED_INITIALIZER;
- (instancetype)initWithCapacity:(NSUInteger)numItems NS_DESIGNATED_INITIALIZER;
- (nullable instancetype)initWithCoder:(NSCoder *)aDecoder NS_DESIGNATED_INITIALIZER;

@end

@interface NSMutableArray<ObjectType> (NSExtendedMutableArray)

- (void)addObjectsFromArray:(NSArray<ObjectType> *)otherArray;
- (void)exchangeObjectAtIndex:(NSUInteger)idx1 withObjectAtIndex:(NSUInteger)idx2;
- (void)removeAllObjects;
- (void)removeObject:(ObjectType)anObject inRange:(NSRange)range;
- (void)removeObject:(ObjectType)anObject;
- (void)removeObjectIdenticalTo:(ObjectType)anObject inRange:(NSRange)range;
- (void)removeObjectIdenticalTo:(ObjectType)anObject;
- (void)removeObjectsFromIndices:(NSUInteger *)indices numIndices:(NSUInteger)cnt NS_DEPRECATED(10_0, 10_6, 2_0, 4_0);
- (void)removeObjectsInArray:(NSArray<ObjectType> *)otherArray;
- (void)removeObjectsInRange:(NSRange)range;
- (void)replaceObjectsInRange:(NSRange)range withObjectsFromArray:(NSArray<ObjectType> *)otherArray range:(NSRange)otherRange;
- (void)replaceObjectsInRange:(NSRange)range withObjectsFromArray:(NSArray<ObjectType> *)otherArray;
- (void)setArray:(NSArray<ObjectType> *)otherArray;
- (void)sortUsingFunction:(NSInteger (NS_NOESCAPE *)(ObjectType,  ObjectType, void * _Nullable))compare context:(nullable void *)context;
- (void)sortUsingSelector:(SEL)comparator;

- (void)insertObjects:(NSArray<ObjectType> *)objects atIndexes:(NSIndexSet *)indexes;
- (void)removeObjectsAtIndexes:(NSIndexSet *)indexes;
- (void)replaceObjectsAtIndexes:(NSIndexSet *)indexes withObjects:(NSArray<ObjectType> *)objects;

- (void)setObject:(ObjectType)obj atIndexedSubscript:(NSUInteger)idx NS_AVAILABLE(10_8, 6_0);

- (void)sortUsingComparator:(NSComparator NS_NOESCAPE)cmptr NS_AVAILABLE(10_6, 4_0);
- (void)sortWithOptions:(NSSortOptions)opts usingComparator:(NSComparator NS_NOESCAPE)cmptr NS_AVAILABLE(10_6, 4_0);

@end

@interface NSMutableArray<ObjectType> (NSMutableArrayCreation)

+ (instancetype)arrayWithCapacity:(NSUInteger)numItems;

+ (nullable NSMutableArray<ObjectType> *)arrayWithContentsOfFile:(NSString *)path;
+ (nullable NSMutableArray<ObjectType> *)arrayWithContentsOfURL:(NSURL *)url;
- (nullable NSMutableArray<ObjectType> *)initWithContentsOfFile:(NSString *)path;
- (nullable NSMutableArray<ObjectType> *)initWithContentsOfURL:(NSURL *)url;