数组是一个有序集合，oc中只能存储对象类型。
下标从0开始，通过下标访问数组元素。
NSArray：创建好后，数组中的元素个数不能发生改变。
NSMutableArray:可变数组.
数组中多个元素用逗号隔开。

//
//  main.m
//  OC04_数组字典集合
//
//  Created by lanou3g on 17/7/31.
//  Copyright © 2017年 lanou3g. All rights reserved.
//

#import <Foundation/Foundation.h>

int main(int argc, const char * argv[]) {
    
    //数组：OC中的数组只能存储对象类型，必能存储int,float这些基础类型
    //不可变数组：不能改变元素个数
    NSArray *arr = [[NSArray alloc] initWithObjects:@"one",@"two",@"three", nil];
    NSArray *arr2 = [NSArray arrayWithObjects:@"one",@"two",@"three", nil];
    NSArray *arr3 = @[@"one",@"two",@"three"];
    //数组元素个数
    NSLog(@"%ld",arr.count);
    //从数组中取索引位置对应的元素
    NSLog(@"array中索引值为0处的元素：%@",[arr2 objectAtIndex:0]);
    //字面量形式，与上面方法等价
    NSLog(@"%@",arr3[0]);
    //判断数组是否包含一个对象
    if ([arr2 containsObject:@"two"]) {
        NSLog(@"包含");
    }else {
        NSLog(@"不包含");
    }
    //根据对象取索引值(首次出现的)
    NSLog(@"%ld",[arr2 indexOfObject:@"three"]);
    //将一个字符串分割
    NSString *string = @"www.baidu.com";
    NSArray *arr4 = [string componentsSeparatedByString:@"."];
    NSLog(@"%@",arr4);
    //将数组中的字符串合并
    NSArray *arr5 = @[@"北京",@"大连",@"哈尔滨",@"上海",@"广州",@"西安"];
    NSString *string1 = [arr5 componentsJoinedByString:@"&"];
    NSLog(@"%@",string1);
    
    NSString *string2 = @"http://www.imanhua.com/Cover/2011-10/hyrz.jpg&http://www.imanhua.com/Cover/2011-09/op.jpg&http://www.imanhua.com/Cover/2012-04/yjdwb.jpg";
    NSArray *arr6 = [string2 componentsSeparatedByString:@"&"];
    NSLog(@"%@",arr6);
    
    NSArray *arr7 = @[@"type = iOS", @"Device = iPhone", @"count = 11344115@163.com", @"password = 12345"];
    NSString *string3 = [arr7 componentsJoinedByString:@"&"];
    NSLog(@"%@",string3);
    
    //可变数组
    NSMutableArray *muarr1 = [[NSMutableArray alloc] initWithObjects:@"one",@"two",@"three", nil];
    //字面量创建方式（不可变数组拷贝一份可变的副本）
    NSMutableArray *muarr3 = [@[@"one",@"two"] mutableCopy];
    //由一个已知的数组创建另一个数组
    NSMutableArray *muArr1 = [NSMutableArray arrayWithArray:muarr3];
    
    NSMutableArray *muarr2 = [NSMutableArray arrayWithObjects:@"one",@"two",@"three", nil];
    //在数组的末尾处添加一个元素
    [muArr1 addObject:@"liying"];
    NSLog(@"%@",muArr1);
    
    [muArr1 insertObject:@"包子" atIndex:1];
    NSLog(@"%@",muArr1[1]);
    
    //移除一个对象(根据内存地址判定)
    [muArr1 removeObject:@"包子"];
    NSLog(@"%@",muArr1);
    
    //移除最后一个元素
    [muArr1 removeLastObject];
    NSLog(@"%@",muArr1);
    //通过索引位置去移除某个元素
    [muArr1 removeObjectAtIndex:1];
    NSLog(@"%@",muArr1);
    //清空数组
    [muArr1 removeAllObjects];
    NSLog(@"%@",muArr1);
    //修改某索引处的元素内容
    muArr1[0] = @"包包";
    NSLog(@"%@",muArr1);
    //交换两个索引处的元素
    [muarr1 exchangeObjectAtIndex:0 withObjectAtIndex:1];
    
    NSMutableArray *mua  =[NSMutableArray arrayWithObjects:@"one",@"two",@"three", nil];
    [mua addObject:@"five"];
    if ([mua containsObject:@"three"]) {
        NSUInteger index = [mua indexOfObject:@"three"];
        [mua replaceObjectAtIndex:index withObject:@"six"];
        NSLog(@"%@",mua);
        [mua removeObject:@"one"];
        NSLog(@"%@",mua);
    }
   
    [mua removeObject:@"two"];
    NSLog(@"%@",mua);
    
    //创建一个字典(key和value要求都是对象类型，key通常都是字符串，且key是唯一的，不允许两个相同的key出现)
    NSDictionary *dic = [[NSDictionary alloc] initWithObjectsAndKeys:@"包包",@"name",@"24",@"age", nil];//[值，键]
    NSString *name = [dic objectForKey:@"name"];
    NSLog(@"%@",name);
    //字面量写法
    NSDictionary *dic1 = @{@"name":@"olivia",@"age":@"99"};//[键，值]
    NSLog(@"%@",dic1);
    //字典里面取值（字面量写法）
    NSString *namee = dic[@"name"];
    NSLog(@"%@",namee);
    
    return 0;
}