[iOS 多线程 & 网络

A.上传JSON

1.思路：

必须使用POST方法才能上传大量JSON数据

设置请求头：设置Content-Type

设置请求体，JSON实际相当于字典，可以用NSDictionary

NSJSONSerialization把字典数据转换成JSON二进制

2.实现

 1 //
 2 //  ViewController.m
 3 //  PostJsonDemo
 4 //
 5 //  Created by hellovoidworld on 15/1/28.
 6 //  Copyright (c) 2015年 hellovoidworld. All rights reserved.
 7 //
 8 
 9 #import "ViewController.h"
10 
11 @interface ViewController ()
12 - (IBAction)postJson;
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 - (IBAction)postJson {
24     // 1.创建请求
25     NSURL *url = [NSURL URLWithString:@"http://192.168.0.21:8080/MyTestServer/acceptJson"];
26     NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];
27     // 设置post发送
28     request.HTTPMethod = @"POST";
29    
30     // 2.设置请求头
31     [request setValue:@"application/json" forHTTPHeaderField:@"Content-Type"];
32    
33     // 3.设置请求体
34     NSDictionary *json = @{@"name":@"tom",
35                            @"age":@"21"};
36     request.HTTPBody = [NSJSONSerialization dataWithJSONObject:json options:NSJSONWritingPrettyPrinted error:nil];
37    
38    
39     // 4.发送请求
40     [NSURLConnection sendAsynchronousRequest:request queue:[NSOperationQueue mainQueue] completionHandler:^(NSURLResponse *response, NSData *data, NSError *connectionError) {
41         NSLog(@"%@", [NSJSONSerialization JSONObjectWithData:data options:NSJSONReadingMutableLeaves error:nil]);
42     }];
43    
44 }
45 @end

B.多值参数

1.概念

一个参数名对应多个参数值

http://localhost:8080/MyTestServer/upload?type=aaa&type=bbb&type=ccc

这样在服务器接收到的就是一个数组