1 #pragma mark 返回Get登录请求
 2 - (NSURLRequest *)getLoginRequest
 3 {
 4     NSString *userName = _userName.text;
 5     NSString *password = [_password.text companyMD5];
 6     NSLog(@"%@", [_password.text MD5]);
 7     NSLog(@"%@", password);
 8
 9     // 1. 网络地址URL
10     NSString *urlString = [NSString stringWithFormat:@"http://192.168.3.251/~apple/itcast/login.php?username=%@&password=%@", userName, password       ];
11     urlString = [urlString stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
12
13     NSURL *url = [NSURL URLWithString:urlString];
14
15     // 2. 请求
16     // 1> url
17     // 2> 缓存策略
18     // 3> 超时时长
19     // 提示：因为网络的状态是未知的，因此要使用URLRequest一定要指定超时时长
20     // 否则会严重影响用户体验！
21     return [NSURLRequest requestWithURL:url cachePolicy:NSURLRequestUseProtocolCachePolicy timeoutInterval:2.0f];
22
23 }
24
25
26 #pragma mark Get方法登录
27 - (IBAction)getLogin
28 {
29     // 1. 建立请求
30     NSURLRequest *request = [self getLoginRequest];
31
32     // 3. 连接
33     NSURLConnection *connection = [NSURLConnection connectionWithRequest:request delegate:self];
34
35     // 4. 启动连接
36     [connection start];
37
38     // 5. 实例化接收数据
39     _serverData = [NSMutableData data];
40 }

 1 - (IBAction)postLogin
 2 {
 3     NSString *userName = _userName.text;
 4     NSString *password = _password.text;
 5
 6     // 1. 网络地址URL
 7     NSString *urlString = [NSString stringWithFormat:@"http://192.168.3.251/~apple/itcast/login.php"];
 8
 9     NSURL *url = [NSURL URLWithString:urlString];
10
11     // 2. 请求，生成数据体添加到请求
12     NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];
13
14     // 1) 指定网络请求的方法
15     // 默认是GET，POST请求通常用在用户登录，上传文件
16     request.HTTPMethod = @"POST";
17
18     // 2) 生成数据体
19     NSString *bodyStr = [NSString stringWithFormat:@"username=%@&password=%@", userName, password];
20     // 转换成NSData
21     request.HTTPBody = [bodyStr dataUsingEncoding:NSUTF8StringEncoding];
22
23     // 3. 连接
24     NSURLConnection *connection = [NSURLConnection connectionWithRequest:request delegate:self];
25
26     // 4. 启动连接
27     [connection start];
28
29     // 5. 实例化接收数据
30     _serverData = [NSMutableData data];
31 }