当我使用iPhone执行HTTP POST请求时，HTTP标头消失

Question

i am new to Objective c and i stuck in a problem which only appears when i do HTTP POST request.
I do HTTP request with my iPhone and i expect the server returns me something like this in the header (this is the respond header from other server):

{
"Cache-Control" = "no-store, no-cache, must-revalidate, post-check=0, pre-check=0";
Connection = close;
"Content-Length" = 0;
"Content-Type" = "text/html";
Date = "something";
Expires = "something";
Location = "/mylocation/10"; <--- this is what i want
Pragma = "no-cache";
Server = "Apache/2.2.3 (CentOS)";
"Set-Cookie" = "something";
"X-Powered-By" = "PHP/5.3.3";
}

When i do a successful posting ,it does the function that is want and returns an empty response with a header like this:

{
"Cache-Control" = "max-age=0, no-cache";
Connection = close;
"Content-Length" = 0;
"Content-Type" = "text/html";
Date = "something";
Server = "Apache/2.2.14 (Ubuntu)";
}

Even i add the headers like "Cache-Control" = "no-store, no-cache, must-revalidate, post-check=0, pre-check=0", they will not be displayed in the respond header.
What should i do to get the correct header?

Additional information
I use ASIFormDataRequest to make request, here is the code that i set header:

{
__block ASIFormDataRequest *request = [ASIFormDataRequest requestWithURL:something];
[request setRequestMethod:@"POST"];
[request addRequestHeader:@"Authorization" value:@"something"];
[request addRequestHeader:@"Accept" value:@"application/json,*/*;q=0.8"];
[request addRequestHeader:@"Content-Type" value:@"application/json"];
}

And this is how i get the respond headers:

{
[request startSynchronous];
NSLog(@"%@", [request responseHeaders]);
}

Answer 1

Location headers will be sent only during the time of redirection. When we add a resource using PUT method the newly created URL will be added in the Location header and will be sent as part of the response. This also happens during 3xx redirection.