IOS网络第二天 - 06-POST请求

#import "HMViewController.h"
#import "MBProgressHUD+MJ.h"

@interface HMViewController ()
@property (weak, nonatomic) IBOutlet UITextField *username;
@property (weak, nonatomic) IBOutlet UITextField *pwd;
- (IBAction)login;
@end

@implementation HMViewController

- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
}

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
[self.view endEditing:YES];
}

- (IBAction)login {
// 1.用户名
NSString *usernameText = self.username.text;
if (usernameText.length == 0) {
[MBProgressHUD showError:@"请输入用户名"];
return;
}

// 2.密码
NSString *pwdText = self.pwd.text;
if (pwdText.length == 0) {
[MBProgressHUD showError:@"请输入密码"];
return;
}

// 增加蒙板
[MBProgressHUD showMessage:@"正在拼命登录中...."];

// 3.发送用户名和密码给服务器(走HTTP协议)
// 创建一个URL ： 请求路径
NSURL *url = [NSURL URLWithString:@"http://localhost:8080/MJServer/login"];

// 创建一个请求
NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];

// 5秒后算请求超时（默认60s超时）
request.timeoutInterval = 15;

request.HTTPMethod = @"POST";
// 设置请求体
NSString *param = [NSString stringWithFormat:@"username=%@&pwd=%@", usernameText, pwdText];
// NSString --> NSData
request.HTTPBody = [param dataUsingEncoding:NSUTF8StringEncoding];

// 设置请求头信息
[request setValue:@"iPhone 6" forHTTPHeaderField:@"User-Agent"];

// 发送一个同步请求(在主线程发送请求)
// queue ：存放completionHandler这个任务
NSOperationQueue *queue = [NSOperationQueue mainQueue];
[NSURLConnection sendAsynchronousRequest:request queue:queue completionHandler:
^(NSURLResponse *response, NSData *data, NSError *connectionError) {
// 隐藏蒙板
[MBProgressHUD hideHUD];

//         NSHTTPURLResponse *resp = (NSHTTPURLResponse *)response;
//         NSString *msg = [NSHTTPURLResponse localizedStringForStatusCode:resp.statusCode];
//         NSLog(@"%d %@ %@", resp.statusCode, msg, resp.allHeaderFields);

// 这个block会在请求完毕的时候自动调用
if (connectionError || data == nil) { // 一般请求超时就会来到这
[MBProgressHUD showError:@"请求失败"];
return;
}

// 解析服务器返回的JSON数据
NSDictionary *dict = [NSJSONSerialization JSONObjectWithData:data options:NSJSONReadingMutableLeaves error:nil];
NSString *error = dict[@"error"];
if (error) {
// {"error":"用户名不存在"}
// {"error":"密码不正确"}
[MBProgressHUD showError:error];
} else {
// {"success":"登录成功"}
NSString *success = dict[@"success"];
[MBProgressHUD showSuccess:success];
}
}];
}
@end