1 //
2 // main.m
3 // NSDictionary
4 //
5 // Created by dingxiaowei on 13-5-15.
6 // Copyright (c) 2013年 dingxiaowei. All rights reserved.
7 //
8
9 #import <Foundation/Foundation.h>
10 #import "Student.h"
11 #pragma mark - 字典的创建
12 void dicCreate(){
13 //NSDictionary一旦创建是不可变的 可变的是NSMutableDictionary
14 //创建一个键值对
15 NSDictionary *dic=[NSDictionary dictionaryWithObject:@"dingxiaowei" forKey:@"10141303"]; //只能放OC对象，不能放基本数据类型 注意：不能处理中文
16 //创建多个键值对(最常用的初始化方法)
17 dic=[NSDictionary dictionaryWithObjectsAndKeys:@"cl",@"10141301",
18 @"cey",@"10141302",
19 @"dxw",@"10141303", nil];
20 //其他创建方法
21 NSArray *objs=[NSArray arrayWithObjects:@"v1",@"v2",@"v3", nil];
22 NSArray *keys=[NSArray arrayWithObjects:@"k1",@"k2",@"k3", nil];
23 dic=[NSDictionary dictionaryWithObjects:objs forKeys:keys];
24 NSLog(@"字典是：%@",dic);
25 }
26 #pragma mark - 字典的用法
27 void dicUse(){
28 //创建多个键值对(最常用的初始化方法)
29 NSDictionary *dic=[NSDictionary dictionaryWithObjectsAndKeys:
30 @"v1",@"k1",
31 @"cey",@"10141302",
32 @"dxw",@"10141303", nil];
33 NSLog(@"count:%zi",[dic count]);
34 //由于NSDictionary是不可变的，所以一旦创建只能查询，不能更改
35 id obj=[dic objectForKey:@"k1"];
36 NSLog(@"k1-%@",obj);
37
38 //将字典写入文件中
39 NSString *path=@"/Users/dingxiaowei/Desktop/dictionary.xml";
40 if([dic writeToFile:path atomically:YES]){
41 NSLog(@"字典写入到文件成功");
42 }
43 //读取xml的字典文件
44 dic=[NSDictionary dictionaryWithContentsOfFile:path];
45 NSLog(@"文件读取成功\ndic:%@",dic);
46
47 //返回所有的keys和values
48 NSArray *keys=[dic allKeys];
49 NSArray *values=[dic allValues];
50 NSLog(@"所有的keys是：%@\n所有的值是：%@",keys,values);
51
52 //查询一个value对于的多个key
53 dic=[NSDictionary dictionaryWithObjectsAndKeys:@"v1",@"k1",@"v2",@"k2",@"v1",@"k3",nil];
54 keys=[dic allKeysForObject:@"v1"];
55 NSLog(@"keys:%@",keys);
56
57 //根据多个key取出对于的value
58 //注意：当key找不到对于的value时候，就用marker来代替
59 NSArray *array1=[NSArray array];
60 array1=[dic objectsForKeys:[NSArray arrayWithObjects:@"k1",@"k2", @"k4",nil] notFoundMarker:@"not-found"];//如果找不到对于的object 就用marker代替 比如这儿没有k4
61 NSLog(@"找到的值%@",array1);
62 }
63 #pragma mark - 遍历字典
64 void dicFor(){
65 //初始化字典
66 NSDictionary *dic=[NSDictionary dictionaryWithObjectsAndKeys:@"v1",@"k1",@"v2",@"k2",@"v3",@"k3", nil];
67 //遍历字典所有的key
68 for (id key in dic) {
69 id value=[dic objectForKey:key];
70 NSLog(@"普通遍历：%@-%@",key,value);
71 }
72
73 //key迭代器遍历
74 NSEnumerator *enumer=[dic keyEnumerator];
75 id key=nil;
76 while (key=[enumer nextObject]) {
77 id value=[dic objectForKey:key];
78 NSLog(@"key迭代器遍历：%@-%@",key,value);
79 }
80
81 //value迭代器
82 //对象迭代器
83 //[dic objectEnumerator];
84
85 //lblock遍历(每调遍历一次键值就调用一次block
86 [dic enumerateKeysAndObjectsUsingBlock:^(id key, id obj, BOOL *stop) {
87 NSLog(@"block迭代器遍历：%@-%@",key,obj);
88 }];
89 }
90 #pragma mark - 字典的内存管理
91 void dicMemory(){
92 Student *stu1=[Student studentWithName:@"cl"];
93 Student *stu2=[Student studentWithName:@"cey"];
94 Student *stu3=[Student studentWithName:@"dxw"];
95 //字典会自动销毁，一般静态创建的对象都不需要我们自己释放，自动释放的时候会对key和value对象进行一次release操作
96 NSDictionary *dic=[NSDictionary dictionaryWithObjectsAndKeys:stu1,@"k1",stu2,@"k2",stu3,@"k3",nil]; //注意：把一个对象塞给字典时会进行一次retain时候
97 /*[stu1 retain];
98 [stu2 retain];
99 [stu3 retain];*/
100
101
102 NSLog(@"dic%@",dic);
103 }
104
105 int main(int argc, const char * argv[])
106 {
107
108 @autoreleasepool {
109
110 //dicCreate();
111 //dicUse();
112 //dicFor();
113 dicMemory();
114 }
115 return 0;
116 }
Student.h
1 #import <Foundation/Foundation.h>
2
3 @interface Student : NSObject
4 @property(nonatomic,retain)NSString *name;
5 +(id)studentWithName:(NSString *)name;
6 @end
Student.m
1 #import "Student.h"
2
3 @implementation Student
4
5
6 +(id)studentWithName:(NSString *)name{
7 Student *stu=[[[Student alloc] init] autorelease];
8 stu.name=name;
9 return stu
10 }
11
12 -(NSString *)description{
13 return _name;
14 }
15
16 -(void)dealloc{
17 NSLog(@"名字为%@被销毁了",_name);
18 [_name release];
19 [super dealloc];
20 }
21
22 @end
