使用NSURLSession

NSURLSession总结 

文件上传方法中body处需要填写request的请求体

#define XMGBoundary @"520it"
#define XMGEncode(string) [string dataUsingEncoding:NSUTF8StringEncoding]
#define XMGNewLine [@"\r\n" dataUsingEncoding:NSUTF8StringEncoding]
#import "ViewController.h"
@interface ViewController ()
/** session */
@property (nonatomic, strong) NSURLSession *session;
@end
@implementation ViewController
- (NSURLSession *)session
{
    if (!_session) {
    NSURLSessionConfiguration *cfg = [NSURLSessionConfiguration defaultSessionConfiguration];
    cfg.timeoutIntervalForRequest = 10;
   // 是否允许使用蜂窝网络（手机自带网络）
   cfg.allowsCellularAccess = YES;
   _session = [NSURLSession sessionWithConfiguration:cfg];
   }  
   return _session;
}
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
    NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:[NSURL URLWithString:@"http://120.25.226.186:32812/upload"]];
    request.HTTPMethod = @"POST";
    // 设置请求头(告诉服务器,这是一个文件上传的请求)
    [request setValue:[NSString stringWithFormat:@"multipart/form-data; boundary=%@", XMGBoundary]forHTTPHeaderField:@"Content-Type"];
    // 设置请求体
    NSMutableData *body = [NSMutableData data];
    // 文件参数
    // 分割线
    [body appendData:XMGEncode(@"--")];
    [body appendData:XMGEncode(XMGBoundary)];
    [body appendData:XMGNewLine];
    // 文件参数名
    [body appendData:XMGEncode([NSString stringWithFormat:@"Content-Disposition: form-data; name=\"file\";filename=\"test.png\""])];
    [body appendData:XMGNewLine];
    // 文件的类型
    [body appendData:XMGEncode([NSString stringWithFormat:@"Content-Type: image/png"])];
    [body appendData:XMGNewLine];
    // 文件数据
     [body appendData:XMGNewLine];
     [body appendData:[NSData dataWithContentsOfFile:@"/Users/xiaomage/Desktop/test.png"]];
     [body appendData:XMGNewLine];
    // 结束标记
    /*
    --分割线--\r\n
    */
    [body appendData:XMGEncode(@"--")];
    [body appendData:XMGEncode(XMGBoundary)];
    [body appendData:XMGEncode(@"--")];
    [body appendData:XMGNewLine];
     [[self.session uploadTaskWithRequest:request fromData:body completionHandler:^(NSData *data, NSURLResponse *response, NSError *error)
        {
           NSLog(@"-------%@", [NSJSONSerialization JSONObjectWithData:data options:kNilOptions error:nil]);
           }] resume];
}
@end