网络处理

self.data = [NSMutableData data];
    
    NSURL *url = [NSURL URLWithString:@"http://192.168.1.106:8080/MJServer/login"];
    NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];
    
    request.HTTPMethod = @"POST";
    
    // 设置请求体
    NSString *param = @"username=hello&pwd=123&type=XML";
    request.HTTPBody = [param dataUsingEncoding:NSUTF8StringEncoding];
    
    // 请求头信息可以省略，只要设置了请求体就OK        
    NSURLConnection *conn = [NSURLConnection connectionWithRequest:request delegate:self];
    [conn start];

  //当服务器返回数据时调用
  // 解析服务器返回的数据
- (void)connectionDidFinishLoading:(NSURLConnection *)connection {
    NSString *str = [[[NSString alloc] initWithData:self.data encoding:NSUTF8StringEncoding] autorelease];
    NSLog(@"%@", str);
}