字典，集合

NSDictionary *dictionary = [[NSDictionary alloc] initWithObjectsAndKeys:@"value1", @"key1", @"value2", @"key2", @"v3", @"k3", @"v5", @"k5", @"v4", @"k4", @"value6", @"key6", @"value7", @"ke7", nil];

NSLog(@"%@", dictionary);

//  使用类方法创建

NSDictionary *dictionary2 = [NSDictionary dictionaryWithObjectsAndKeys:@"v1", @"k1", @"v2", @"k2", nil];

NSLog(@"%@", dictionary2);

NSDictionary *dictionary3 = [NSDictionary dictionaryWithObject:@"value" forKey:@"key"];

NSLog(@"%@", dictionary3);

NSArray *keyArray = [NSArray arrayWithObjects:@"k1", @"k2", @"k3", nil]; //  存放键的数组

NSArray *valueArray = [NSArray arrayWithObjects:@"v1", @"v2", @"v3", nil];//  存放值的数组

NSDictionary *dictionary4 = [NSDictionary dictionaryWithObjects: keyArray forKeys:valueArray];

NSLog(@"%@", dictionary4);

// 创建空字典

NSDictionary *dic = [NSDictionary dictionary];

//  使用一个文件创建字典对象 新建文件步骤：command + N -> Resource -> Property List

NSDictionary *dictionary5 = [NSDictionary dictionaryWithContentsOfFile:@"/Users/lanou3g/Desktop/OC/lesson5-20140425/lesson5-20140425/dictionary.plist"];

NSLog(@"%@", dictionary5);

//  返回字典中键值对的个数

NSLog(@"%ld", [dictionary5 count]);

//  字典取值 获取指定key对应的value

NSString *value1 = [dictionary5 objectForKey:@"ly"];

NSLog(@"%@", value1);

//  返回所有的key数组

NSArray *allKeysArray = [dictionary5 allKeys];

NSLog(@"%@", allKeysArray);

//  返回所有的value数组

NSArray *allValuesArray = [dictionary5 allValues];

NSLog(@"%@", allValuesArray);

//  使用key枚举器(获取所有key)

NSEnumerator *enumerator = [dictionary5 keyEnumerator];

NSString *str = nil;

while (str = [enumerator nextObject]) {

    NSLog(@"%@", str);

}

4.2创建可变字典 NSMutableDictionary

NSMutableDictionary *dic1 = [NSMutableDictionary dictionaryWithObjectsAndKeys:@"v1", @"k1", @"v2", @"k2", nil];

NSMutableDictionary *dic2 = [NSMutableDictionary dictionaryWithObjectsAndKeys:@"v3", @"k3", @"v4", @"k4", @"v5", @"k5", nil];

//  用于整理对象的拼接

[dic1 addEntriesFromDictionary:dic2];

NSLog(@"%@", dic1);

//  删除字典中某个对象

[dic1 removeObjectForKey:@"k1"];

NSLog(@"%@", dic1);

//  删除字典全部对象

[dic1 removeAllObjects];

NSLog(@"%@", dic1);

//  设置字典

[dic1 setDictionary:dic2];

NSLog(@"%@", dic1);

5.1NSSet集合对象 容器类

//  1. 使用类方法创建对象

NSSet *set1 = [NSSet set];  //  创建一个空的集合对象

NSSet *set2 = [NSSet setWithObject:@"abc"];

NSSet *set3 = [NSSet setWithObjects:@"abc", @"aaa", @"bbb", nil];

NSLog(@"%@", set3);

NSArray *array = [NSArray arrayWithObjects:@"a",@"b", @"c", nil];

NSSet *set4 = [NSSet setWithArray:array];   //  使用数组创建

NSLog(@"%@", set4);

NSSet *set5 = [NSSet setWithSet:set4];      //  使用集合创建

NSLog(@"%@", set5);

//  2.使用实例方法创建

NSSet *set6 = [[NSSet alloc] init];

NSLog(@"%@", set6);

NSSet *set7 = [[NSSet alloc] initWithObjects:@"hello", @"hhaa", @"bbjdh", nil];

NSLog(@"%@", set7);

NSSet *set8 = [[NSSet alloc] initWithArray:array];

NSLog(@"%@", set8);

NSSet *set9 = [[NSSet alloc] initWithSet:set7];

NSLog(@"%@", set9);

//  3.返回几个元素个数

NSLog(@"%ld", [set7 count]);

//  4.枚举器访问集合元素

NSEnumerator *enumerator = [set7 objectEnumerator];

NSString *str = nil;

while (str = [enumerator nextObject]) {

    NSLog(@"%@", str);

}

//  5.判断两个几个是否有交集

BOOL ifhasIntersection = [set2 intersectsSet:set3];

NSLog(@"%d", ifhasIntersection);

//  6.判断两个集合是否相等

NSLog(@"%d", [set2 isEqualToSet:set3]);

//  7.判断当前集合是否是子集

NSLog(@"%d", [set2 isSubsetOfSet:set3]);

5.2可变集合 NSMutableSet

//  创建指定元素个数的一个集合对象

NSMutableSet *mutableSet = [NSMutableSet setWithCapacity:4];

[mutableSet addObject:@"aaa"];

NSLog(@"%@", mutableSet);

//  类方法创建可变集合

NSMutableSet *mutableSet1 = [NSMutableSet setWithObjects:@"aaa", @"bbb", @"ccc", nil];

NSMutableSet *mutableSet2 = [NSMutableSet setWithObject:@"aaa"];

//  添加一个对象到集合

[mutableSet2 addObject:@"ddd"];

NSLog(@"%@", mutableSet2);

//  从集合中删除一个对象

[mutableSet2 removeObject:@"ddd"];

NSLog(@"%@", mutableSet2);

//  把数组对象添加到集合对象中

NSArray *arr = [NSArray arrayWithObjects:@"eee", @"fff", nil];

[mutableSet1 addObjectsFromArray:arr];

NSLog(@"%@", mutableSet1);

//  得到两个集合的交集 注意intersectSet和intersectsSet的区别，后者是判断是否有交集的方法， 返回的是bool值

[mutableSet1 intersectSet:mutableSet2];

NSLog(@"%@", mutableSet1);

//  从一个集合中减去另一个集合

[mutableSet1 minusSet:mutableSet2];

NSLog(@"%@", mutableSet1);

//  从一个元素中删除所有元素

[mutableSet2 removeAllObjects];

NSLog(@"%@", mutableSet2);

//  取两个集合的并集

[mutableSet1 unionSet:mutableSet2];

NSLog(@"%@", mutableSet1);

NSLog(@"%@", mutableSet1);

//  设置给集合赋值

[mutableSet1 setSet:mutableSet2];

NSLog(@"%@", mutableSet1);

关于数组排序

NSArray *array = [NSArrayarrayWithObjects:@"12", @"454", @"7878", @"77122", @"555", @"9", nil];

NSLog(@"排序前：%@", array);

//  这样排序是按照字符串大小来排序的不是数值排序

array = [array sortedArrayUsingSelector:@selector(compare:)];

NSLog(@"排序后：%@", array);

//  进行数值排序需要用以下的方法

array = [array sortedArrayUsingFunction:intSort context:NULL];

NSLog(@"排序后：%@", array);

以下是intSort 的方法实现：

NSInteger intSort(id num1, id num2, void *context)

{

    int v1 = [num1 intValue];

    int v2 = [num2 intValue];

    if (v1 < v2)

    returnNSOrderedAscending;

    else if (v1 > v2)

    returnNSOrderedDescending;

    else

    returnNSOrderedSame;

}

关于字典与数组

/// 字典里可以存数组，数组可以存字典

NSArray *arr = [NSArray arrayWithObjects: @"1", @"2", @"3", nil];

//  把数组arr放在字典dic里

NSDictionary *dic = [NSDictionary dictionaryWithObject:arr forKey:@"array"];

NSLog(@"%@", dic);

//  把字典dic和数组arr 放在数组arr2里

NSArray *arr2 = [NSArray arrayWithObjects:arr, dic, nil];

NSLog(@"%@", arr2);

字典，集合