个人整理--OC中的数组

//OC中的数组存放的一定是对象NSArray *arr = [[NSArray alloc]init];//用便利构造器的方式创建一个空数组NSArray *arr = [NSArray array];//字面量的方式NSArray *arr = @[@"1",@"2",@"3",@"4",@"5"];//.count:能够读出数组中元素个数.NSLog(@"%ld",arr.count);//取值也是通过下标进行取值,返回的是一个对象;NSLog(@"%@",[arr objectAtIndex:1]);NSLog(@"%@",arr[1]);//for 对数组进行遍历for (NSInteger i = 0 ; i < arr.count ; i ++){NSLog(@"%@",arr[i]);}NSLog(@"%@",[arr containsObject:@"6"]);

 Student *stu1 = [[Student alloc]initWithName:@"刘鑫奇"]; Student *stu2 = [[Student alloc]initWithName:@"高薪茹"]; Student *stu3 = [[Student alloc]initWithName:@"高小妖精"]; Student *stu4 = [[Student alloc]initWithName:@"高大贱人"]; NSArray *arr = [[NSArray alloc]initWithObjects:stu1,stu2,stu3,stu4, nil];    //用便利构造器的方式创建NSArray *arr = [NSArray arrayWithObjects:stu1,stu2,stu3,stu4,nil];    //快速枚举:能快速的遍历数组等容器对象    //都是对容器中的每一个元素的遍历    //为了增加代码的阅读性,避免不必要的错误,尽量让 forin的前部分的类型和数组里元素类型相同  for (NSString *str in arr) {        NSLog(@"%@",str);   }   NSArray *arr1 = @[@"刘鑫奇",@"刘山山",@"刘星宇",@"刘能"];   NSArray *arr2 = @[@"腾飞",@"周胜民",@"商帅",@"郭洪瑞"];   NSArray *arr = @[arr1 , arr2];//对arr进行forin遍历    for (NSArray *temp in arr){        for (NSString *str in temp){            NSLog( @"%@",str);        }    }    Student *stu1 = [[Student alloc]initWithName:@"刘鑫奇"];    Student *stu2 = [[Student alloc]initWithName:@"高薪茹"];    Student *stu3 = [[Student alloc]initWithName:@"高小妖精"];    Student *stu4 = [[Student alloc]initWithName:@"高大贱人"];    NSArray *arr1 = @[stu1,stu2,stu3];    NSArray *arr2 = @[stu4];    NSArray *arr = @[arr1 , arr2];    //遍历数组里每一个学生的姓名    for (Student *temp in arr) {        for (Student *stu in temp) {            NSLog(@"%@",stu.name);            }    }

 //可变数组     NSMutableArray *arr = [[NSMutableArray alloc]init];     NSMutableArray *arr1 = [[NSMutableArray alloc]initWithObjects:@"1",@"2",@"3",@"4", nil];//添加一个字符串//添加到数组的最后一位    [arr addObject:@"8"];    NSLog(@"%@",arr);//移除下标2的字符串    [arr removeObjectAtIndex:2];    NSLog(@"%@",arr);//替换一个字符串    [arr replaceObjectsAtIndexes:1 withObject:@"7"];    NSLog(@"%@",arr);//交换两个字符串    [arr exchangeObjectAtIndex:1 withObjectAtIndex:4];    NSLog(@"替换%@",arr);//清空数组    [arr removeAllObjects];    NSLog(@"清空%@",arr);

    Book *book1 = [Book bookWithbookName:@"西游记" bookPrice:30];    Book *book2 = [Book bookWithbookName:@"水浒传" bookPrice:25];    Book *book3 = [Book bookWithbookName:@"三国演义" bookPrice:35];    Book *book4 = [Book bookWithbookName:@"金瓶梅(插图版)" bookPrice:40];    //四本书放在一个可变数组中    NSMutableArray *bookArr = [NSMutableArray arrayWithObjects:book1,book2,book3,book4, nil];    //    2、数组可以添加、删除书籍。    Book *book5 = [Book bookWithbookName:@"红楼梦" bookPrice:38];    [bookArr addObject:book5];    for (Book *book in bookArr) {        NSLog(@"%@ , %ld",book.bookName,book.bookPrice);    }    [bookArr removeObject:book5];    for (Book *book0 in bookArr) {        NSLog(@"%@ ,%ld ",book0.bookName , book0.bookPrice);    }    for (Book *temp in bookArr) {       if ([temp.bookName isEqualToString:@"红楼梦"]) {            temp.bookPrice = 150;        }    }    for (Book *temp in bookArr) {       NSLog(@"%@,%ld",temp.bookName,temp.bookPrice);    }