【OC05-2】NSSet、NSNumber、NSValue、NSDate、异常处理（连载七）

//************* NSSet ********************************
       
        //不可变集合
        //初始化集合
        //集合中没有重复的元素，而且无序
        NSSet *set = [[NSSet alloc]initWithObjects:@"1",@"2", nil];
        NSLog(@"set is %@",set);
       
        //类方法初始化
        NSSet *set1 = [NSSet setWithObjects:@"1",@"2",@"x",@"y", nil];
        NSLog(@"set1 is %@",set1);
       
        //获取集合中元素的个数
        NSInteger count = [set1 count];
        NSLog(@"count is %ld",count);
       
        //获取集合中所有元素
        NSArray *list = [set1 allObjects];
        NSLog(@"list is %@",list);
       
        //获取集合中任意一个元素
        id value = [set1 anyObject];
        NSLog(@"value is %@",value);
       
        //判断集合中是否包含某各元素
        BOOL isTrue = [set1 containsObject:@"x"];
        NSLog(@"isTrue is %d",isTrue);
       
        //*******************************************
        //可变集合
        NSMutableSet *mutableSet1 = [NSMutableSet set];
        NSLog(@"mutableSet is %@",mutableSet1);
       
        //添加元素
        [mutableSet1 addObject:@"x"];
        NSLog(@"mutableSet is %@",mutableSet1);
       
        //批量添加
        NSArray *arr = @[@"1", @"2", @"3", @"3",];
        [mutableSet1 addObjectsFromArray:arr];
        NSLog(@"mutableSet is %@",mutableSet1);
       
        //删除元素
        [mutableSet1 removeObject:@"x"];
        NSLog(@"mutableSet is %@",mutableSet1);
       
        //删除所有元素
//        [mutableSet1 removeAllObjects];
//        NSLog(@"mutableSet is %@",mutableSet1);
       
       
        //集合的遍历
        //传统遍历
        //需先将集合中的元素转入数组
        NSArray *arr1 = [mutableSet1 allObjects];
        for (int i = 0; i < mutableSet1.count; i++) {
            NSString *str = arr1[i];
            //注意：不可以通过下标取集合中的元素
//            NSString *str = mutableSet1[1];
            NSLog(@"%@",str);
        }
       
        NSLog(@"------------------------");
        //快速遍历
        for (id value in mutableSet1) {
            NSLog(@"%@",value);

        }

//************ NSNumber *************************
       
        //封装基本数据类型
        int intValue = 10;
        float floatValue = 3.23;
        BOOL boolValue = true;
       
        NSNumber *intNum = [[NSNumber alloc]initWithInt:intValue];
        NSNumber *floatNum = [[NSNumber alloc]initWithFloat:floatValue];
        NSNumber *boolNum = [[NSNumber alloc]initWithBool:boolValue];
       
        NSLog(@"intNum is %@, floatNum is %@, boolNum is %@",intNum, floatNum, boolNum);
       
        //包装后可以放到容器中
        NSArray *arr = @[intNum, floatNum, boolNum];
        NSLog(@"arr is %@",arr);
       
        //还原为基本数据类型
        int value1 = [intNum intValue];
        float value2 = [floatNum floatValue];
        BOOL value3 = [boolNum boolValue];
       
        NSLog(@"value1 is %d, value2 is %.2f, value3 is %d",value1, value2, value3);

       

//************ NSValue **************************

        //NSValue可以包含任意类型
       
        //创建一个结构体
        NSRange range = {1,4};
       
        //将结构体包装成对象
        NSValue *value = [NSValue value:&range withObjCType:@encode(NSRange)];
        NSLog(@"value is %@",value);
       
        //还原结构体
        NSRange newRange;
        [value getValue:&newRange];
        NSLog(@"newRange.location is %ld,newRange.length is %ld",newRange.location,newRange.length);
       
        NSLog(@"newRange is %@",NSStringFromRange(newRange));
       
        //NSNull
        //表示一个空对象
        NSNull *null = [NSNull alloc];
        NSArray *arr = @[@"1", @"2",null,@"4"];

        NSLog(@"arr is %@",arr);

//*********** NSDate ********************************
       
        //获取当前系统时间  标准时间 GMT 格林尼治时间
        NSDate *date = [NSDate date];
        NSLog(@"date is %@",date);
       
        NSDate *date1 = [[NSDate alloc]init];
        NSLog(@"date1 is %@",date1);
       
        //获取时间戳
        NSTimeInterval time1970 = [date timeIntervalSince1970];
        NSLog(@"time1970 is %.2f",time1970);
       
        //到当前世纪（2001）的时间
        NSTimeInterval time2001 = [date timeIntervalSinceReferenceDate];
        NSLog(@"time2010 is %.2f",time2001);
       
        //到当前的时间
        NSTimeInterval time = [date timeIntervalSinceNow];
        NSLog(@"time is %.2f",time);
       
        //获取昨天的时间
        NSTimeInterval oneDay = 24 * 60 * 60;//先计算出一天的秒数
        NSDate *yesterday = [[NSDate alloc]initWithTimeIntervalSinceNow:-oneDay];
        NSLog(@"yestoday is %@",yesterday);
       
        //获取明天的时间
        NSDate *tommorrow = [[NSDate alloc]initWithTimeIntervalSinceNow:oneDay];
        NSLog(@"tommorrow is %@",tommorrow);
       
        //获取将来的时间（最大值）
        NSDate *future = [NSDate distantFuture];
        NSLog(@"future is %@",future);
       
        //获取过去的时间
        NSDate *past = [NSDate distantPast];
        NSLog(@"past is %@",past);
       
       
        //============ 日期的比较 =============================
       
        //比较两个时间是否相同----（无意义）
        BOOL isEqual = [date isEqualToDate:date1];
        NSLog(@"isEqual is %d",isEqual);
       
        //返回两个时间中较早的那个时间
        NSDate *earlierDate = [tommorrow earlierDate:yesterday];
        NSLog(@"earlierDate is %@",earlierDate);
       
        //返回两个时间中较晚的那个时间
        NSDate *laterDate = [tommorrow laterDate:yesterday];
        NSLog(@"laterDate is %@",laterDate);
       
        //====================================================
        //------------- 重要！！！------------------------------
        //将时间戳转换成日期
        NSTimeInterval seconed = 1234567890;
        NSDate *date2 = [NSDate dateWithTimeIntervalSince1970:seconed];
        NSLog(@"date2 is %@",date2);
       
        //格式化日期类
        NSDateFormatter *df = [[NSDateFormatter alloc]init];
        [df setDateFormat:@"yyyy年MM月dd日  HH时mm分ss秒  ZZZZ"];
       
        //将日期按照格式化类型转换成字符串
        NSString *str = [df stringFromDate:date];
        NSLog(@"str is %@",str);
       
        //将字符串格式化为日期
        NSDate *date3 = [df dateFromString:str];

        NSLog(@"date3 is %@",date3);

//*********** 异常处理 ******************************
       
        NSArray *array = @[@"1", @"2"];
        @try {
            //尝试着去执行以下代码，看编译器是否会报错
            NSLog(@"%@",array[2]);
        }
        @catch (NSException *exception) {
            //如果捕获到异常，则执行以下代码
            NSLog(@"exception name is %@, reson is %@",exception.name, exception.reason);
        }
        @finally {
            //不管是否捕获到异常，都会执行
            NSLog(@"finally");
        }