ASIHTTPRequest 是一个直接在CFNetwork上做的开源项目，提供了一个比官方更方便更强大的HTTP网络传输的封装。它的特色功能如下：
1，下载的数据直接保存到内存或文件系统里 2，提供直接提交(HTTP POST)文件的API 3，可以直接访问与修改HTTP请求与响应HEADER 4，轻松获取上传与下载的进度信息 5，异步请求与队列，自动管理上传与下载队列管理机 6，认证与授权的支持 7，Cookie 8，请求与响应的GZIP 9，代理请求 下面来两个ASIHTTPRequest的小例子：NSURL *url = [NSURL URLWithString:@"http://www.baidu.com"];
ASIHTTPRequest *request = [ASIHTTPRequest requestWithURL:url]; [request start]; NSError *error = [request error]; if (!error) { NSString *response = [request responseString]; } 当你需要添加更多的请求信息时，如，添加个请求Header： [request addRequestHeader:@"name" value:@"Jory lee"]; 添加Post请求时的健值: [request setPostValue:@"Ben" forKey:@"first_name"]; [request setPostValue:@"Copsey" forKey:@"last_name"]; [request setFile:@"/Users/ben/Desktop/ben.jpg" forKey:@"photo"]; 设置HTTP的授权帐号： [request setUsername:@"username"]; [request setPassword:@"password"]; 一个异步请求： - (IBAction)grabURLInBackground:(id)sender { NSURL *url = [NSURL URLWithString:@"http://allseeing-i.com"]; ASIHTTPRequest *request = [ASIHTTPRequest requestWithURL:url]; [request setDelegate:self]; [request startAsynchronous]; } - (void)requestFinished:(ASIHTTPRequest *)request { // Use when fetching text data NSString *responseString = [request responseString]; // Use when fetching binary data NSData *responseData = [request responseData]; } - (void)requestFailed:(ASIHTTPRequest *)request { NSError *error = [request error]; } 在我们数据获取的过程中，如果数据源复杂，一个请求队列是必不可少的： - (IBAction)grabURLInTheBackground:(id)sender { if (![self queue]) { [self setQueue:[[[NSOperationQueue alloc] init] autorelease]]; } NSURL *url = [NSURL URLWithString:@"http://allseeing-i.com"]; ASIHTTPRequest *request = [ASIHTTPRequest requestWithURL:url]; [request setDelegate:self]; [request setDidFinishSelector:@selector(requestDone:)]; [request setDidFailSelector:@selector(requestWentWrong:)]; [[self queue] addOperation:request]; //queue is an NSOperationQueue } - (void)requestDone:(ASIHTTPRequest *)request { NSString *response = [request responseString]; } - (void)requestWentWrong:(ASIHTTPRequest *)request { NSError *error = [request error]; }另外大家可以通过下面这个代码例子，看 ASIHTTP 比传统的 post 方法的方便之处
post用法
NSString *post = @"这里放要传递的参数"; NSData *postData = [post dataUsingEncoding:NSASCIIStringEncoding allowLossyConversion:YES]; NSString *postLength = [NSString stringWithFormat:@"%d", [postData length]]; NSMutableURLRequest *request = [[[NSMutableURLRequest alloc] init] autorelease]; [request setURL:[NSURL URLWithString:@"请求地址"]]; [request setHTTPMethod:@"POST"]; [request setValue:postLength forHTTPHeaderField:@"Content-Length"]; //[request addValue:@"gzip" forHTTPHeaderField:@"Accepts-Encoding"]; [request setValue:@"application/x-www-form-urlencoded" forHTTPHeaderField:@"Content-Type"]; [request setHTTPBody:postData]; NSURLConnection *conn=[[NSURLConnection alloc] initWithRequest:request delegate:self]; if (conn) { receivedbData = [[NSMutableData data] retain]; } else { // inform the user that the download could not be made } ASIHTTP 方法 NSURL *url = [NSURL URLWithString:@"请求地址"]; //ASIHTTPRequest *request = [ASIHTTPRequest requestWithURL:url]; ASIFormDataRequest *request=[ASIFormDataRequest requestWithURL:url]; [request setPostValue:@"值" forKey:@"参数1"]; [request setPostValue:@"值" forKey:@"参数2"]; [request start]; NSError *error = [request error]; if (!error) { NSString *response = [request responseString]; NSLog(response); } 相比之下，ASIHTTP 的确省了很多代码。更多信息请访问官方网站