NSDictionary使用小结

日志:

1. NSArray *m_array = [NSArray arrayWithObjects:@"first",@"second",nil];
2. NSArray *n_array = [NSArray arrayWithObjects:@"one",@"two",@"three",nil];
3. //使用类方法初始化,系统自动释放内存
4. NSDictionary *test_dictionary = [NSDictionary dictionaryWithObjectsAndKeys:m_array,@"sort",n_array,@"number",nil];

1. //获取字典包含对象数目
2. int dict_size = [test_dictionary count];
3. //访问字典中的值
4. NSArray *sort_array = [test_dictionary objectForKey:@"sort"];
5. //获取键值
6. NSArray *keys = [test_dictionary allKeysForObject:sort_array];
7. //获取字典中所有值，数组
8. NSArray *all_value = [test_dictionary allValues];
9. //快速枚举
10. for(id key in test_dictionary)
11. {
12. NSLog(@"key: %@,value: %@",key,[test_dictionary objectForKey:key]);
13. }
14. //如果字典只包含属性列表对象(NSData,NSDate,NSNumber,NSString,NSArray或NSDictionary)可以保存到文件中
15. NSString *filePath = [[[NSBundlemainBundle]resourcePath]stringByAppendingPathComponent:@"test_dict.plist"];
16. [test_dictionary writeToFile:filePath atomically:YES];
17. //用文件填充
18. NSDictionary *myDict =[NSDictionary dictionaryWithContentsOfFile:filePath];
19. //可变字典
20. NSMutableDictionary *dictMutable = [[NSMutableDictionary alloc]initWithObjectsAndKeys:m_array,@"sort",n_array,@"number", nil];
21. NSString *str = @"10_10";
22. //修改对象
23. [dictMutable setObject:string4 forKey:@"sort"];
24. //删除对象
25. [dictMutable removeObjectForKey:@"number"];
26. //删除多个对象
27. NSArray *key_array =[NSArray arrayWithObjects:@"sort",@"number", nil];
28. [dictMutable removeObjectForKey:key_array];
29. //删除所有对象
30. [dictMutable removeAllObjects];

//k-v 键值对

//key:对象标识符，不重复

//value:对象，可重复

//字典与数组的区别：数组有序，字典无序；

//分 可变字典 不可变字典

//创建三个person对象

Person *person1 = [Person PersonWithName:@"xi" age:18];

Person *person2 = [Person PersonWithName:@"aa" age:9];

Person *person3 = [Person PersonWithName:@"ao" age:3];

//将对象添加到字典中

//

NSDictionary *pDict = [[NSDictionary alloc]initWithObjectsAndKeys:

person1,@"xi",

person2,@"aa",

person3,@"ao",   nil];

//便利构造器

NSDictionary *pD = [NSDictionary dictionaryWithObjects:@[person1,person2,person3] forKeys:@[@"xi",@"aa",@"ao"]];

NSLog(@"%@",pDict);

//字面量创建 不可变

NSDictionary *pDict1 = @{ @"xi":person1,

@"aa":person2,

@"ao":person3 };

NSLog(@"%@",pDict);

NSLog(@"%@",pDict);

NSLog(@"-----------------使用枚举器，便利-------------------------");

NSEnumerator *keyEnum = [pDict1 keyEnumerator];

id obj;

while (  obj = [keyEnum nextObject]) {

NSLog(@"key=%@",obj);

}

NSEnumerator *keyEnum1 = [pDict1 objectEnumerator];

id obj1;

while (  obj1 = [keyEnum1 nextObject]) {

NSLog(@"value=%@",obj1);

}

NSLog(@"-----------------使用枚举器，便利-------------------------");

//从字典取出一个对象

Person *p = [pDict objectForKey:@"xi"];

Person *p1 = pDict[@"xi"];

NSLog(@"%@",p);

NSLog(@"%@",p1);

//打印所有key

NSLog(@"key=%@",[pDict allKeys]);

//打印所有value

NSLog(@"value=%@",[pDict allValues]);

//循环的打印字典中的键值对

for (int i = 0; i < pDict.count; i++) {

//先通过循环 从allkeys 数组 取出每一个key

NSString *key = [pDict allKeys][i];

Person *p = pDict[key];

NSLog(@"key=%@,value=%@",key, p);//调用description方法

}

//可变字典

//1,创建

NSMutableDictionary *mutaDic = [NSMutableDictionary dictionary];

NSMutableDictionary *mutaDic1 = [NSMutableDictionary dictionaryWithObjectsAndKeys:person1,@"ao",person2,@"xi", nil];

//2，添加

[mutaDic1 setObject:person3 forKey:@"aa"];

//3，替换

[mutaDic1 setObject:person3 forKey:@"ao"];

//4，根据key去删除value

[mutaDic1 removeObjectForKey:@"ao"];

//5，删除所有

[mutaDic1 removeAllObjects];

//

//

for (int i = 0; i < mutaDic1.count; i++) {

//先通过循环 从allkeys 数组 取出每一个key

NSString *key = [mutaDic1 allKeys][i];

Person *p = mutaDic1[key];

NSLog(@"key=%@,value=%@",key, p);//调用description方法

}

//1,创建一个数组，

NSArray *classArray = @[@"zhang",@"zhu"];

//2,创建一个数组，

NSArray *classArray1 = @[@"zha",@"zh"];

//1,创建一个大数组，

NSArray *classArrayB = @[classArray,classArray1];

NSDictionary *allClassDict = @{@"36": classArray,

@"37": classArray1,

};

NSLog(@"%@",allClassDict[@"36"][0]);

//NSset  元素唯一，无序，随机抽取，

//1,

NSSet *set = [NSSet setWithObjects:@"c",@"d",@"a", nil];

NSLog(@"%@",set);

NSLog(@"%@",[set anyObject]);

if ([set containsObject:@"c"]) {

NSLog(@"you c");

}

//1,创建 年龄数组

NSArray *ageArray = @[@12, @33, @65];

//使用数组创建集合

NSCountedSet *ageSet = [NSCountedSet setWithArray:ageArray];

//年龄是33的个数

NSLog(@"%lu",[ageSet countForObject:@33 ]);

//快速枚举

NSArray *arr = @[@"wang",@"jin",@"wei",@11];

for (id a in arr) {

NSLog(@"%@",a);

}

NSDictionary *dict = @{@"11": @"v1",

@"22": @"v2"};

//默认取key

for (NSString * key in dict) {

NSLog(@"%@",key);

}

//取value的值

for (NSString * value in [dict allValues]) {

NSLog(@"%@",value);

}

//创建一个保存年龄的数组

NSMutableArray *mArr = [NSMutableArray arrayWithObjects:@"12", @"2", @"9", @"21", nil];

for (int  i = 0; i < mArr.count - 1; i++) {

for (int j = 0; j < mArr.count - 1 - i; j++) {

if ([mArr[j] intValue] >  [mArr[j+1] intValue]) {

[mArr exchangeObjectAtIndex:j withObjectAtIndex:j+1];

}

}

}

NSLog(@"%@",mArr);

//默认升序

[mArr sortedArrayUsingSelector:@selector(compare:)];

NSLog(@"%@",mArr);

//    //创建三个person对象

//    Person *person1 = [Person PersonWithName:@"xi" age:18];

//    Person *person2 = [Person PersonWithName:@"aa" age:19];

//    Person *person3 = [Person PersonWithName:@"ao" age:38];

//

NSMutableArray *personArray = [NSMutableArray arrayWithObjects:person1, person2, person3, nil];

NSLog(@"%@",personArray);

//按年龄从小到大排序

for (int i = 0; i < personArray.count - 1; i++) {

for (int j = 0; j < personArray.count - i - 1;j++) {

if ([personArray[j] age] > [personArray[j + 1] age] ) {

[personArray exchangeObjectAtIndex:j withObjectAtIndex:j + 1];

}

}

}

NSLog(@"%@",personArray);

NSDictionary的常见用法总结

NSArray *array1 = [NSArray arrayWithObjects:@"iphone",@"ipod",nil];

NSArray *array2 = [NSArray arrayWithObjects:@"mac",@"imac",@"mac pro",nil];

//类方法初始化自动释放

NSDictionary *myDictionary = [NSDictionary dictionaryWithObjectsAndKeys:array1,@"mobile",array2,@"computers",nil];//注意用nil结束

NSLog(@"myDictionary = %@",myDictionary);

int dictSize = [myDictionary count];

//访问字典中的值

NSArray *mobile = [myDictionary objectForKey:@"mobile"];

//从一个对象获取键

NSArray *keys = [myDictionary allKeysForObject:array1];

//获取字典中所有值得一个数组

NSArray *values = [myDictionary allValues];

//快速枚举

for(id key in myDictionary)

{

NSLog(@"key: %@,value: %@",key,[myDictionary objectForKey:key]);

}

//如果字典只包含属性列表对象(NSData,NSDate,NSNumber,NSString,NSArray或NSDictionary)可以保存到文件中

NSString *filePath = [[[NSBundlemainBundle]resourcePath]stringByAppendingPathComponent:@"dict.txt"];

BOOL success = [myDictionary writeToFile:filePath atomically:YES];

//用文件填充

NSDictionary *myDict2 =[NSDictionary dictionaryWithContentsOfFile:filePath];

//可变字典

NSMutableDictionary *dictMutable = [[NSMutableDictionary alloc]initWithObjectsAndKeys:array1,@"mobile",array2,@"computer", nil];

NSString *string4 = @"stringTV";

//修改对象

[dictMutable setObject:string4 forKey:@"media"];

//删除对象

[dictMutable removeObjectForKey:@"mobile"];

//删除多个对象

NSArray *keyArray =[NSArray arrayWithObjects:@"mobile",@"computer", nil];

[dictMutable removeObjectForKey:keyArray];

//删除所有对象

[dictMutable removeAllObjects];

注: iOS 6 新的快捷初始化写法:

NSDictionary:

NSMutableDictionary:

1:基础初始化

2:为字典添加对象(键与值都是 id 接受任何类型)

3:通过键取得值对象

4:删除某个对象