Iphone 带参数的Http Post请求

我有一个简单的asp.net web服务，它返回json格式的数据。我想发送带有参数的http post请求以获取json数据如何发送请求并获取数据？

发布请求：

POST /JsonWS.asmx/FirmaGetir HTTP/1.1
Host: localhost
Content-Type: application/x-www-form-urlencoded
Content-Length: length

firID=string

HTTP/1.1 200 OK
Content-Type: text/xml; charset=utf-8
Content-Length: length    
<?xml version="1.0" encoding="utf-8"?>
<string xmlns="http://tempuri.org/">string</string>

回答：

POST /JsonWS.asmx/FirmaGetir HTTP/1.1
Host: localhost
Content-Type: application/x-www-form-urlencoded
Content-Length: length

firID=string

HTTP/1.1 200 OK
Content-Type: text/xml; charset=utf-8
Content-Length: length    
<?xml version="1.0" encoding="utf-8"?>
<string xmlns="http://tempuri.org/">string</string>

---

你在这里干什么

[[NSURLConnection alloc] initWithRequest:request delegate:self];

此行返回一个NSURLConnection，但您没有存储它。这对你毫无帮助

在读取数据之前，您正在清除数据：

-(void)connectionDidFinishLoading:(NSURLConnection *)connection
{
    response = [[NSMutableData data] retain]; // This line is clearing your data get rid of it
    NSString *responseString = [[NSString alloc] initWithData:response encoding:NSUTF8StringEncoding];
    NSLog(@"%@",responseString);

}

编辑

-(IBAction)buttonClick:(id)sender {

    NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:[NSURL URLWithString:@"http://192.168.1.23/testService/JsonWS.asmx?op=FirmaGetir"]
                                                           cachePolicy:NSURLRequestReloadIgnoringLocalAndRemoteCacheData
                                                       timeoutInterval:15];
    [request setHTTPMethod:@"POST"];
    [request setValue:@"application/x-www-form-urlencoded" forHTTPHeaderField:@"Content-Type"];
    [request setHTTPBody:[@"firID=800" dataUsingEncoding:NSUTF8StringEncoding]];
    self.connection = [[NSURLConnection alloc] initWithRequest:request delegate:self];
    [self.connection start];

}


#pragma NSURLConnection Delegates

- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data {

    if (!self.receivedData){
        self.receivedData = [NSMutableData data];
    }
    [self.receivedData appendData:data];
}

- (void)connectionDidFinishLoading:(NSURLConnection *)connection {

     NSString *responseString = [[NSString alloc] initWithData:self.receivedData encoding:NSUTF8StringEncoding];
     NSLog(@"%@",responseString);
}

---

今天早上我遇到了这个问题，现在我才明白。我想你问题的关键是如何使用带有参数的POST方法。其实很简单

（1） 首先，您应该确保您的文件已准备好发送。这里我们说它是一个名为stringReady的NSString。我们将其用作名为postRequest的方法中的一个参数（这里不是我们要讨论的HTTP POST参数。别担心）

（2）现在，我们说服务器想要获取的参数称为“数据”，这是将参数插入HTTP正文的方式。

NSString *firmadi =@"";
NSMutableData *response;


-(IBAction)buttonClick:(id)sender
{
    NSString *firid = [NSString stringWithFormat:@"800"];

    response = [[NSMutableData data] retain];

    NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:[NSURL URLWithString:@"http://192.168.1.23/testService/JsonWS.asmx?op=FirmaGetir"]];

    NSString *params = [[NSString alloc] initWithFormat:@"firID=%@",firid];
    [request setHTTPMethod:@"POST"];
    [request setHTTPBody:[params dataUsingEncoding:NSUTF8StringEncoding]];
    [request setValue:@"application/x-www-form-urlencoded" forHTTPHeaderField:@"Content-Type"];
    [[NSURLConnection alloc] initWithRequest:request delegate:self];
NSURLConnection *theConnection = [[NSURLConnection alloc] initWithRequest:request delegate:self];

    if(theConnection)
    {
        response = [[NSMutableData data] retain];

    }
    else 
    {
        NSLog(@"theConnection is null");
    }

}

-(void)connection:(NSURLConnection*)connection didReceiveResponse:(NSURLResponse*)responsed
{
    [response setLength:0];
     NSURLResponse * httpResponse;

    httpResponse = (NSURLResponse *) responsed;

}

-(void)connection:(NSURLConnection *)connection didReceiveData:(NSData*)data
{
    [response appendData:data];
    //NSLog(@"webdata: %@", data);

}

-(void)connection:(NSURLConnection *)connection didFailWithError:(NSError*)error
{
    NSLog(@"error with the connection");
    [connection release];
    [response release];
}

-(void)connectionDidFinishLoading:(NSURLConnection *)connection
{

    response = [[NSMutableData data] retain];

 NSString *responseString = [[NSString alloc] initWithData:response encoding:NSUTF8StringEncoding];
    NSLog(@"%@",responseString);

}

// Add the [data] parameter
NSString *bodyWithPara = [NSString stringWithFormat:@"data=%@",stringReady];

请看，这是使用POST方法时添加参数的方式。只需将参数放在要发送的文件之前。如果您知道您的参数，那么您最好查看以下网站：

这将帮助您测试是否正确发送文件，并在网站底部显示响应

（3） 第三，我们将NSString打包到NSData并将其发送到服务器

// Convert the String to NSData
NSData *postData = [bodyWithPara dataUsingEncoding:NSASCIIStringEncoding allowLossyConversion:YES];
// Set the content length and http body
NSString *postLength = [NSString stringWithFormat:@"%lu",(unsigned long)[postData length]];
[req addValue:postLength forHTTPHeaderField:@"Content-Length"];
[req setValue:@"application/x-www-form-urlencoded" forHTTPHeaderField:@"Content-Type"];
[req setHTTPBody:postData];
// Create an NSURLSession
NSURLSession *session = [NSURLSession sharedSession];
NSURLSessionDataTask *task = [session dataTaskWithRequest:req
                                        completionHandler:^(NSData *data, NSURLResponse *response, NSError *error) {
                                            // Do something with response data here - convert to JSON, check if error exists, etc....
                                            if (!data) {
                                                NSLog(@"No data returned from the sever, error occured: %@", error);
                                                return;
                                            }

                                            NSLog(@"got the NSData fine. here it is...\n%@\n", data);
                                            NSLog(@"next step, deserialising");

                                            NSError *deserr;
                                            NSDictionary *responseDict = [NSJSONSerialization
                                                                          JSONObjectWithData:data
                                                                          options:kNilOptions
                                                                          error:&deserr];
                                            NSLog(@"so, here's the responseDict\n\n\n%@\n\n\n", responseDict);
                                        }];

[task resume];}

---

希望这能帮助陷入困境的人。

您是否尝试过将请求中的MIME类型设置为“application/json”而不是“application/x-www-form-urlencoded”？它来自我的web服务，为什么我要更改此设置？您发布的代码有什么问题？屏幕上有一个按钮。当我按下按钮时，我想看到我的服务结果。但是没有发生。在didFinishLoading response=[[NSMutableData]retain]中，您在使用之前下载的所有数据都将丢失，请将其放在NSString*responseString之后…感谢关注。我是ios开发新手。因此，在我的代码中有一些愚蠢的代码块。我问问题就是为了这个原因。我将尝试这些，但请编写此过程的完整代码。谢谢，我明天将尝试。我找到了不同的解决方案，但我接受您的回答，以引起您的注意。是NSURLConnection sendAsynchronousRequest:queue:completionHandler:？有几种不同的解决方案。我发布的是基于你发布的内容。它非常适合身份验证和定制。sendAsynchronousRequest:queue:completionHandler:适用于简单的异步调用。连接不需要调用start。除非使用-（id）initWithRequest:（NSURLRequest*）请求委托：（id）委托立即开始：（BOOL）startimimediately with startimimediately=NO，否则它将立即启动