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//
2 // ViewController.m
3 // NSURLCacheDemo
4 //
5 // Created by haomengzhu on 15/1/28.
6 // Copyright (c) 2015年 haomengzhu. All rights reserved.
7 //
8
9 #import "ViewController.h"
10
11 @interface ViewController ()
12 - (IBAction)downloadData;
13
14 @end
15
16 @implementation ViewController
17
18 - (void)viewDidLoad {
19 [super viewDidLoad];
20 // Do any additional setup after loading the view, typically from a nib.
21 }
22
23 - (void)didReceiveMemoryWarning {
24 [super didReceiveMemoryWarning];
25 // Dispose of any resources that can be recreated.
26 }
27
28 - (IBAction)downloadData {
29 // 1.创建请求
30 NSURL *url = [NSURL URLWithString:@"http://192.168.0.21:8080/MyTestServer/video?type=json"];
31 NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];
32
33 // 2.设置缓存策略
34 request.cachePolicy = NSURLRequestReturnCacheDataElseLoad; // 有缓存就不请求
35
36 // 获得全局缓存
37 NSURLCache *cache = [NSURLCache sharedURLCache];
38
39 // 定期处理缓存
40 // if (超过一定时期) {
41 // [cache removeCachedResponseForRequest:request];
42 // }
43
44 // 获得某个request的response
45 NSCachedURLResponse *response = [cache cachedResponseForRequest:request];
46 if (response) {
47 NSLog(