iOS开发之OC篇（3）—— NSArray、NSMutableArray

版本

Xcode 8.2.1

一、不可变数组NSArray

老规矩，先贴上知识点，再打个例子和举个比方。    

//使用arrayWithObjects创建NSArray

    NSArray *arr = [NSArray arrayWithObjects:@"abc",@"def",@"123",nil];

//    NSArray *arr = [[NSArray alloc] initWithObjects:@"111",@"ddd",@"234",nil];

    

    //使用arrayWithArray创建NSArray

    NSArray *arr1 = [NSArray arrayWithArray:arr];

//    NSArray *arr1 = [[NSArray alloc]initWithArray:arr];

    

    //使用@创建NSArray,只能创建不可变数组

    NSArray *arr2 = @[@"aaaa",@"bbb",@"ddddd"];

    NSLog(@"arr2 = %@",arr2);

    

    //返回元素个数

    NSLog(@"arr2 count = %ld",[arr2 count]);

    

    //返回指定位置id

    NSString *str0 = [arr2 objectAtIndex:2];

    NSLog(@"str0 = %@",str0);

    

    //访问数组的最后一个元素

    NSString *str = [arr2 lastObject];

    NSLog(@"str = %@",str);

    

    //访问数组的第一个元素

    NSString *str1 = [arr firstObject];

    NSLog(@"str1 = %@",str1);

    

    //判断数组内是否含有某一个对象

    if([arr containsObject:@"123"]) {

        NSLog(@"含有此对象");

    }

    

    //获取某个对象在数组中的下标值

    NSUInteger index = [arr indexOfObject:@"123"];

    

    //数组的遍历

    for(NSInteger i =0;i < [arr count]; i++) {

        NSLog(@"arr[%ld] = %@",i,arr[i]);

    }

    

    //快速枚举法(快速遍历)

    for(id objin  arr) {

        NSLog(@"obj = %@",obj);

    }

int main(int argc, char * argv[]) {
    
    //使用arrayWithObjects创建NSArray
    NSArray *arr = [NSArray arrayWithObjects:@"ABC",@"DEF",@"GHI",nil];
        //NSArray *arr = [[NSArray alloc] initWithObjects:@"ABC",@"DEF",@"GHI",nil];
    NSLog(@"arr = %@",arr);
    
    //使用arrayWithArray创建NSArray
    NSArray *arr1 = [NSArray arrayWithArray:arr];
        //NSArray *arr1 = [[NSArray alloc]initWithArray:arr];
    NSLog(@"arr1 = %@",arr1);
    
    //使用@创建NSArray,只能创建不可变数组
    NSArray *arr2 = @[@"123",@"456",@"789"];
    NSLog(@"arr2 = %@",arr2);
    
    //返回元素个数
    NSLog(@"arr count = %ld",[arr count]);
    
    //返回指定位置id
    NSString *str = [arr objectAtIndex:1];
    NSLog(@"str = %@",str);
    
    //访问数组的第一个元素
    NSString *strF = [arr firstObject];
    NSLog(@"strF = %@",strF);
    
    //访问数组的最后一个元素
    NSString *strL = [arr lastObject];
    NSLog(@"strL = %@",strL);
    
    //判断数组内是否含有某一个对象
    if ([arr2 containsObject:@"456"]) {
        NSLog(@"数组arr2内含有对象456");
    }
    
    //获取某个对象在数组中的下标值
    NSUInteger index = [arr indexOfObject:@"ABC"];
    NSLog(@"ABC下标值为%ld",index);
    
    //数组的遍历
    for (NSInteger i = 0; i < [arr count]; i++) {
        NSLog(@"arr[%ld] = %@",i,arr[i]);
    }
    
    //快速枚举法(快速遍历)
    for (id arr2Q in arr2) {
        NSLog(@"arr2Q = %@",arr2Q);
    }

}

输出结果：

二、可变数组NSMutableArray

    //实例化一个空的可变数组

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

    

    //添加一个元素

    [nsarr addObject:@"ONE"];

    NSLog(@"nsarr = %@",nsarr);

    

    //添加多个元素

    [nsarr addObjectsFromArray:@[@"ONE",@"TWO",@"THREE"]];

    NSLog(@"nsarr = %@",nsarr);

    

    //插入元素

    [nsarr insertObject:@"Two" atIndex:1];

    NSLog(@"nsarr = %@",nsarr);

    

    //替换元素

    [nsarr replaceObjectAtIndex:0 withObject:@"1"];

    NSLog(@"nsarr = %@",nsarr);

    

    //查询元素

    NSString *result = [nsarr objectAtIndex:1];//arr[1]

    NSLog(@"result = %@",result);

    

    //删除指定元素

    [nsarr removeObject:@"ONE"];

    NSLog(@"nsarr = %@",nsarr);

    

    //删除指定下标的元素

    [nsarr removeObjectAtIndex:2];

    NSLog(@"nsarr = %@",nsarr);

    

    //删除最后一个元素

    [nsarr removeLastObject];

    NSLog(@"nsarr = %@",nsarr);

    

    //删除所有元素

    [nsarr removeAllObjects];

    NSLog(@"nsarr = %@",nsarr);

    

    //删除数组中含有的所有元素

    [nsarr removeObjectsInArray:@[@"1",@"THREE"]];

    

    //交换元素

    NSMutableArray *nsarr1 = [NSMutableArray arrayWithObjects:@"1",@"2",@"3",nil];

    [nsarr1 exchangeObjectAtIndex:1 withObjectAtIndex:2];

    NSLog(@"nsarr1 = %@",nsarr1);

    

    //切割字符串

    NSString *str3 = @"I am a super man + beautiful, yeah!";

    //用指定的字符串进行切割

    NSArray *rArr = [str3 componentsSeparatedByString:@" "];

    NSLog(@"rArr = %@",rArr);

    

    //实例化一个字符集合

    NSCharacterSet *set = [NSCharacterSet  characterSetWithCharactersInString:@" ,+"];

    //按照字符集合所提供的字符进行切割

    NSArray *rArr2 = [str3 componentsSeparatedByCharactersInSet:set];

    NSLog(@"rArr2 = %@",rArr2);

    

    //拼接数组内的字符串

    NSString *str2 = [rArr2 componentsJoinedByString:@"-"];

    NSLog(@"str2 = %@",str2);

    

    //按照ASCII码大小进行排序,SEL:方法选择器(储存一个方法名)

    NSMutableArray *arr3 = [NSMutableArray arrayWithObjects:@"B",@"A",@"C",@"Z",nil];

    [arr3 sortedArrayUsingSelector:@selector(compare:)];//方法选择器

    

    //按三个人年龄大小排序

    Person *per0 = [[Person alloc]initWith:18];

    Person *per1 = [[Person alloc]initWith:6];

    Person *per2 = [[Person alloc]initWith:60];

    NSMutableArray *perArr = [[NSMutableArray alloc]initWithObjects:per0,per1,per2,nil];

    //compareAge提供一个排序方法，看按什么方式排序

    NSArray *resultPerArr = [perArr sortedArrayUsingSelector:@selector(compareAge:)];

int main(int argc, char * argv[]) {
    
    //实例化一个空的可变数组
    NSMutableArray *arr = [[NSMutableArray alloc]init];
    
    //添加一个元素
    [arr addObject:@"he"];
    NSLog(@"arr = %@",arr);
    
    //添加多个元素
    [arr addObjectsFromArray:@[@"is",@"Chinese"]];
    NSLog(@"arr = %@",arr);

    //插入元素
    [arr insertObject:@"not" atIndex:2];
    NSLog(@"arr = %@",arr);
    
    //以arrayWithArray创建arr1
    NSMutableArray  *arr1 = [NSMutableArray arrayWithArray:arr];

    //替换元素
    [arr replaceObjectAtIndex:3 withObject:@"Japanese"];
    NSLog(@"arr = %@",arr);

    //查询元素
    NSString *result = [arr objectAtIndex:0];
    NSLog(@"arr[0] = %@",result);

    //删除指定元素
    [arr removeObject:@"not"];
    NSLog(@"arr = %@",arr);

    //删除指定下标的元素
    [arr removeObjectAtIndex:1];
    NSLog(@"arr = %@",arr);

    //删除最后一个元素
    [arr removeLastObject];
    NSLog(@"arr = %@",arr);

    //删除所有元素
    [arr removeAllObjects];
    NSLog(@"arr = %@",arr);

    //删除数组中含有的所有元素
    [arr1 removeObjectsInArray:@[@"not",@"is"]];
    NSLog(@"arr1 = %@",arr1);

    //交换元素
    [arr1 exchangeObjectAtIndex:0 withObjectAtIndex:1];
    NSLog(@"arr1 = %@",arr1);

    //切割字符串
    NSString *str1 = @"I am,a super man!";
    //用指定的字符串进行切割
    NSArray *cutArr = [str1 componentsSeparatedByString:@","];
    NSLog(@"cutArr = %@",cutArr);

    //实例化一个字符集合
    NSCharacterSet *set = [NSCharacterSet  characterSetWithCharactersInString:@"super "];
    //按照字符集合所提供的字符进行切割
    NSArray *cutArr2 = [str1 componentsSeparatedByCharactersInSet:set];
    NSLog(@"cutArr2 = %@",cutArr2);

    //拼接数组内的字符串
    NSString *str2 = [cutArr2 componentsJoinedByString:@"-"];
    NSLog(@"str2 = %@",str2);
 /*
    //按照ASCII码大小进行排序,SEL:方法选择器(储存一个方法名)
    NSMutableArray *arr3 = [NSMutableArray arrayWithObjects:@"B",@"A",@"C",@"Z",nil];
    [arr3 sortedArrayUsingSelector:@selector(compare:)]; //方法选择器
    
    //按三个人年龄大小排序
    Person *per0 = [[Person alloc]initWith:18];
    Person *per1 = [[Person alloc]initWith:6];
    Person *per2 = [[Person alloc]initWith:60];
    NSMutableArray *perArr = [[NSMutableArray alloc]initWithObjects:per0,per1,per2,nil];
    //compareAge提供一个排序方法，看按什么方式排序
    NSArray *resultPerArr = [perArr sortedArrayUsingSelector:@selector(compareAge:)];
 */
}

输出结果：

注：NSArray和NSMutableArray只能存储OC对象。