Foundation框架中NSArray和NSMutableArray

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=================== NSArray ====================（不可变数组，一旦建立就不能被更改）

Ordered collection of objects. Immutable(you cannot add or remove objects to it once it’s created)
Important methods:
+ (id)arrayWithObjects:(id)firstObject, ...;    // nil terminated 
- (int)count;                                                      // 得到array中的对象个数
- (id)objectAtIndex:(int)index;                       //  得到索引为i的对象

- (BOOL)containsObject:(id)anObject;      // 当anObject出现在array中，则返回yes（实际是通过isEqual:方法来判断）

- (unsigned)indexOfObject:(id)anObject; // 查找array中的anObject,并返回其最小索引值。没找到返回NSNotFound.

- (void)makeObjectsPerformSelector:(SEL)aSelector;

- (NSArray *)sortedArrayUsingSelector:(SEL)aSelector;
- (id)lastObject;                                         // 得到array中最后一个对象。如果array中没有任何对象存在，则返回nil
注：
类方法arrayWithObjects 可以创建an autoreleased NSArray of the items.例如
@implementation MyObject
- (NSArray *)coolCats {
return [NSArray arrayWithObjects:@“Steve”, @“Ankush”, @“Sean”, nil];
}
@end
Other convenient create with methods (all return autoreleased objects):
[NSString stringWithFormat:@“Meaning of %@ is %d”, @“life”, 42];
[NSDictionary dictionaryWithObjectsAndKeys:ankush, @“TA”, janestudent, @“Student”, nil];
[NSArray arrayWithContentsOfFile:(NSString *)path];
-----创建数组 -----
    NSArray *array = [[NSArray alloc] initWithObjects:@"One",@"Two",@"Three",@"Four",nil];

    self.dataArray = array;
    NSLog(@"self.dataArray count is:%d",[self.dataArray count]);

    NSLog(@"self.dataArray index 2 is:%@",[self.dataArray objectAtIndex:2]);

------ 从一个数组拷贝数据到另一数组(可变数级) -------   

    //arrayWithArray:
    NSArray *array1 = [[NSArray alloc] init];
    NSMutableArray *MutableArray = [[NSMutableArray alloc] init];
    NSArray *array = [NSArray arrayWithObjects:@"a",@"b",@"c",nil];
    NSLog(@"array:%@",array);
    MutableArray = [NSMutableArray arrayWithArray:array];
    NSLog(@"MutableArray:%@",MutableArray);

    array1 = [NSArray arrayWithArray:array];
    NSLog(@"array1:%@",array1);

    //Copy

    //id obj;
    NSMutableArray *newArray = [[NSMutableArray alloc] init];
    NSArray *oldArray = [NSArray arrayWithObjects:@"a",@"b",@"c",@"d",@"e",@"f",@"g",@"h",nil];

    NSLog(@"oldArray:%@",oldArray);
    for(int i = 0; i < [oldArray count]; i++) {        
        obj = [[oldArray objectAtIndex:i] copy];
        [newArray addObject: obj];
    }
    
    NSLog(@"newArray:%@", newArray);

    //快速枚举
    NSMutableArray *newArray = [[NSMutableArray alloc] init];
    NSArray *oldArray = [NSArray arrayWithObjects:
                         @"a",@"b",@"c",@"d",@"e",@"f",@"g",@"h",nil];   
    NSLog(@"oldArray:%@",oldArray);

    for(id obj in oldArray)

    {
        [newArray addObject: obj];
    }
   
    NSLog(@"newArray:%@", newArray);
  

    //Deep copy

    NSMutableArray *newArray = [[NSMutableArray alloc] init];

    NSArray *oldArray = [NSArray arrayWithObjects:
                         @"a",@"b",@"c",@"d",@"e",@"f",@"g",@"h",nil];   
    NSLog(@"oldArray:%@",oldArray);   
    newArray = (NSMutableArray*)CFPropertyListCreateDeepCopy(kCFAllocatorDefault, (CFPropertyListRef)oldArray, kCFPropertyListMutableContainers);
    NSLog(@"newArray:%@", newArray);
  

=================== NSMutableArray ====================（可变数组）
Mutable version of NSArray.
- (void)addObject:(id)anObject;                                              // 在array最后添加anObject, 添加nil是非法的.
- (void)addObjectsFromArray:(NSArray *)otherArray;         //在array最后把otherArray中的对象依次添加进去。

- (void)insertObject:(id)anObject atIndex:(int)index;          //在索引index处插入anObject, 若index被占用，会把之后的object向后移。

- (void)removeObjectAtIndex:(int)index;                               //删除index处的对象，后面的对象依次向前移。

- (void)removeObject:(id)anObject;                                      // 删除所有和anObject相等的对象，同样使用isEqual:作为相等比较方法.
- (void)removeAllObjects;

注：我们不能把nil加到array中。但有时候我们真想给array加一个空的对象，可以使用NSNull来做这件事。如：

[myArray addObject:[NSNull null]];

Foundation框架中NSArray和NSMutableArray

标签：style   io   使用   ar   strong   for   数据   div   sp   

原文地址：http://www.cnblogs.com/yanyuewen/p/3985027.html