iOS开发网络篇—文件的上传

说明：文件上传使用的时POST请求，通常把要上传的数据保存在请求体中。本文介绍如何不借助第三方框架实现iOS开发中得文件上传。

　　由于过程较为复杂，因此本文只贴出部分关键代码。

主控制器的关键代码：

YYViewController.m

 1 #import "YYViewController.h"  2  3 #define YYEncode(str) [str dataUsingEncoding:NSUTF8StringEncoding]
 4  5 @interface YYViewController ()
 6  7 @end  8  9 @implementation YYViewController
10 11 - (void)viewDidLoad
12 {
13  [super viewDidLoad];
14 // Do any additional setup after loading the view, typically from a nib. 15 }
16 17 - (void)upload:(NSString *)name filename:(NSString *)filename mimeType:(NSString *)mimeType data:(NSData *)data parmas:(NSDictionary *)params 18 {
19 // 文件上传 20 NSURL *url = [NSURL URLWithString:@"http://192.168.1.200:8080/YYServer/upload"];
21 NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];
22 request.HTTPMethod = @"POST";
23 24 // 设置请求体 25 NSMutableData *body = [NSMutableData data];
26 27 /***************文件参数***************/ 28 // 参数开始的标志 29 [body appendData:YYEncode(@"--YY\r\n")];
30 // name : 指定参数名(必须跟服务器端保持一致)
31 // filename : 文件名 32 NSString *disposition = [NSString stringWithFormat:@"Content-Disposition: form-data; name=\"%@\"; filename=\"%@\"\r\n", name, filename];
33  [body appendData:YYEncode(disposition)];
34 NSString *type = [NSString stringWithFormat:@"Content-Type: %@\r\n", mimeType];
35  [body appendData:YYEncode(type)];
36 37 [body appendData:YYEncode(@"\r\n")];
38  [body appendData:data];
39 [body appendData:YYEncode(@"\r\n")];
40 41 /***************普通参数***************/ 42 [params enumerateKeysAndObjectsUsingBlock:^(id key, id obj, BOOL *stop) {
43 // 参数开始的标志 44 [body appendData:YYEncode(@"--YY\r\n")];
45 NSString *disposition = [NSString stringWithFormat:@"Content-Disposition: form-data; name=\"%@\"\r\n", key];
46  [body appendData:YYEncode(disposition)];
47 48 [body appendData:YYEncode(@"\r\n")];
49  [body appendData:YYEncode(obj)];
50 [body appendData:YYEncode(@"\r\n")];
51  }];
52 53 /***************参数结束***************/ 54 // YY--\r\n 55 [body appendData:YYEncode(@"--YY--\r\n")];
56 request.HTTPBody = body;
57 58 // 设置请求头
59 // 请求体的长度 60 [request setValue:[NSString stringWithFormat:@"%zd", body.length] forHTTPHeaderField:@"Content-Length"];
61 // 声明这个POST请求是个文件上传 62 [request setValue:@"multipart/form-data; boundary=YY" forHTTPHeaderField:@"Content-Type"];
63 64 // 发送请求 65 [NSURLConnection sendAsynchronousRequest:request queue:[NSOperationQueue mainQueue] completionHandler:^(NSURLResponse *response, NSData *data, NSError *connectionError) {
66 if (data) {
67 NSDictionary *dict = [NSJSONSerialization JSONObjectWithData:data options:NSJSONReadingMutableLeaves error:nil];
68 NSLog(@"%@", dict);
69 } else {
70 NSLog(@"上传失败");
71  }
72  }];
73 }
74 75 - (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event 76 {
77 // Socket 实现断点上传
78 79 //apache-tomcat-6.0.41/conf/web.xml 查找 文件的 mimeType
80 // UIImage *image = [UIImage imageNamed:@"test"];
81 // NSData *filedata = UIImagePNGRepresentation(image);
82 // [self upload:@"file" filename:@"test.png" mimeType:@"image/png" data:filedata parmas:@{@"username" : @"123"}];
83 84 // 给本地文件发送一个请求 85 NSURL *fileurl = [[NSBundle mainBundle] URLForResource:@"itcast.txt" withExtension:nil];
86 NSURLRequest *request = [NSURLRequest requestWithURL:fileurl];
87 NSURLResponse *repsonse = nil;
88 NSData *data = [NSURLConnection sendSynchronousRequest:request returningResponse:&repsonse error:nil];
89 90 // 得到mimeType 91 NSLog(@"%@", repsonse.MIMEType);
92 [self upload:@"file" filename:@"itcast.txt" mimeType:repsonse.MIMEType data:data parmas:@{
93 @"username" : @"999",
94 @"type" : @"XML"}];
95 }
96 97 @end

补充说明：

文件上传请求数据格式

部分文件的MIMEType