NSURL *url = [NSURL URLWithString:@"https://www.baidu.com"];
NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];
request.HTTPMethod = @"POST";
// 请求参数
NSString *bodyStr = [NSString stringWithFormat:@"username=%@&password=%@", username, password];
request.HTTPBody = [bodyStr dataUsingEncoding:NSUTF8StringEncoding];
NSData *data =[NSURLConnection sendSynchronousRequest:request returningResponse:nil error:nil];
NSError *error = nil;
NSDictionary *json = [NSJSONSerialization JSONObjectWithData:data options:NSJSONReadingMutableLeaves error:&error];
NSLog(@"---------------%@", json);