Nishant is correct. While C++ doesn't provide any specific APIs to "reflect" on WinRT types, these types are fully defined in CLI compliant metadata files and you can use the CLR native metadata APIs to read their definition. One thing you need to figure
out is how to get to the actual winmd for a given type. For that, Win8 provides new metadata discovery APIs (RoGetMetaDataFile).
This won't allow you to do any instantiation or method calls though. So this should rarely be useful in a C++ app.
However, since Marius was asking for a sample, here's a snippet of code that I was playing with. Disclaimer: while I tried to make sure that the snippet works and correctly handles most errors, I might've missed a few things so treat this code with a grain
of salt. :)
#include <windows.h>
#include <hstring.h>
#include <cor.h>
#include <rometadata.h>
#include <rometadataresolution.h>
#include <collection.h>
namespace ABI_Isolation_Workaround {
#include <inspectable.h>
#include <WeakReference.h>
}
using namespace ABI_Isolation_Workaround;
#include <wrl/client.h>
using namespace Microsoft::WRL;
using namespace Windows::Foundation::Collections;
IVector<String^>^ GetTypeMethods(Object^);
MainPage::MainPage()
{
InitializeComponent();
Windows::Foundation::Uri^ uri = ref new Windows::Foundation::Uri("http://buildwindows.com/");
auto methods = GetTypeMethods(uri);
std::wstring strMethods;
std::for_each(begin(methods), end(methods), [&strMethods](String^ methodName) {
strMethods += methodName->Data();
strMethods += L"\n";
});
wprintf(L"%s\n", strMethods.c_str());
}
IVector<String^>^ GetTypeMethods(Object^ instance)
{
HRESULT hr;
HSTRING hStringClassName;
hr = instance->__cli_GetRuntimeClassName(reinterpret_cast<__cli_HSTRING__**>(&hStringClassName)); // internal method name subject to change post BUILD
if (FAILED(hr))
__cli_WinRTThrowError(hr); // internal method name subject to change post BUILD
String^ className = reinterpret_cast<String^>(hStringClassName);
ComPtr<IMetaDataDispenserEx> metadataDispenser;
ComPtr<IMetaDataImport2> metadataImport;
hr = MetaDataGetDispenser(CLSID_CorMetaDataDispenser, IID_IMetaDataDispenser, (LPVOID*)metadataDispenser.GetAddressOf());
if (FAILED(hr))
__cli_WinRTThrowError(hr); // internal method name subject to change post BUILD
HSTRING hStringFileName;
mdTypeDef typeDefToken;
hr = RoGetMetaDataFile(hStringClassName, metadataDispenser.Get(), &hStringFileName, &metadataImport, &typeDefToken);
if (FAILED(hr))
__cli_WinRTThrowError(hr); // internal method name subject to change post BUILD
String^ fileName = reinterpret_cast<String^>(hStringFileName);
HCORENUM hCorEnum = 0;
mdMethodDef methodDefs[2048];
ULONG countMethodDefs = sizeof(methodDefs);
hr = metadataImport->EnumMethods(&hCorEnum, typeDefToken, methodDefs, countMethodDefs, &countMethodDefs);
if (FAILED(hr))
__cli_WinRTThrowError(hr); // internal method name subject to change post BUILD
wchar_t methodName[1024];
ULONG countMethodName;
std::wstring strMethods;
Vector<String^>^ retVal = ref new Vector<String^>();
for(int i = 0; i < countMethodDefs; ++i)
{
countMethodName = sizeof(methodName);
hr = metadataImport->GetMethodProps(methodDefs[i], nullptr, methodName, countMethodName, &countMethodName, nullptr, nullptr, nullptr, nullptr, nullptr);
if (SUCCEEDED(hr))
{
methodName[ countMethodName ] = 0;
retVal->Append(ref new String(methodName));
}
}
return retVal;
}
You'll need to pass Runtimeobject.lib and Rometadata.lib to Linker.
Hope this helps,
Marian Luparu
Visual C++
