Where is CXMLHttpRequest2Callback Declared?

Question

I'm trying to apply the IXHR2 quickstart example in a basic experiment that creates a C++ class that will perform an HTTP GET. I'm running into errors about "undeclared identifiers" right off the bat.

Here is the Quickstart example I'm using...

http://msdn.microsoft.com/en-US/library/windows/apps/xaml/hh770550

Here is my simple C++ class. I added it to a project I created using the Blank App C++ metro app template.

// try_http.cpp

#include "pch.h"
#include "try_http.h"

#include <wrl.h>
#include <wrl/client.h>
#include <wrl/implements.h>
#include <MsXml6.h>
#include <Windows.h>

using namespace Microsoft::WRL;
using namespace Microsoft::WRL::Details;

try_http::try_http(void)
{
}

try_http::~try_http(void)
{
}

void try_http::try_get ()
{

 //http://msdn.microsoft.com/en-US/library/windows/apps/xaml/hh770550
 DWORD dwStatus = 0;
 ComPtr<IXMLHTTPRequest2> spXHR;
 ComPtr<CXMLHttpRequest2Callback> spMyXhrCallback;
 ComPtr<IXMLHTTPRequest2Callback> spXhrCallback;

}

I get 4 erros compiling all reported for this line:

ComPtr<CXMLHttpRequest2Callback> spMyXhrCallback;

Error 1 error C2065: 'CXMLHttpRequest2Callback' : undeclared identifier c:\users\dfran_000\documents\visual studio 2012\projects\httpexperiment\httpexperiment\try_http.cpp 30 1 HTTPExperiment
Error 2 error C2923: 'Microsoft::WRL::ComPtr' : 'CXMLHttpRequest2Callback' is not a valid template type argument for parameter 'T' c:\users\dfran_000\documents\visual studio 2012\projects\httpexperiment\httpexperiment\try_http.cpp 30 1 HTTPExperiment
Error 3 error C2133: 'spMyXhrCallback' : unknown size c:\users\dfran_000\documents\visual studio 2012\projects\httpexperiment\httpexperiment\try_http.cpp 30 1 HTTPExperiment
Error 4 error C2512: 'Microsoft::WRL::ComPtr' : no appropriate default constructor available c:\users\dfran_000\documents\visual studio 2012\projects\httpexperiment\httpexperiment\try_http.cpp 30 1 HTTPExperiment

The "Quickstart" example doesn't actually tell you what any of the headers or namespaces you need are, and I only got this far by searching for other similar questions, but it seems that I'm still lacking whatever header is needed for CXMLHttpRequest2Callback. Anybody know?

Thanks!

Answer 1

I believe CXMLHttpRequest2Callback is provided in the two examples that quickstart is based on (linked in the first paragraph) - e.g. XML HTTP Request 2 GET  sample.  The quickstart is based on those samples and the code snippets are taken directly from them. 

Answer 2

I believe CXMLHttpRequest2Callback is provided in the two examples that quickstart is based on (linked in the first paragraph) - e.g. XML HTTP Request 2 GET sample.  The quickstart is based on those samples and the code snippets are taken directly from them. 

I searched all over in the mentioned sample project, CXMLHttpRequest2Callback does not exist in it. Is there any other answer to the original CrownHill's question, as I have the same problem?

Thanks!

Answer 3

Go to the sample and "Browse Code":

http://code.msdn.microsoft.com/windowsdesktop/XML-HTTP-request-GET-sample-681d6b1e/view/SourceCode#content

It's in XMLHttpRequest2Callback.h and .cpp.