将位图添加到 Windows 运行时剪贴板

如何解决将位图添加到 Windows 运行时剪贴板

我正在开发一个 C++ 应用程序，我需要能够将位图添加到 Windows 运行时剪贴板。我的选择是使用 WRL 或 WinRT，所以我选择了 WRL，因为它似乎有（稍微）更多的文档。经过一番摆弄后，我有一些代码可以将文本添加到剪贴板：

    RoInitializeWrapper initialise(RO_INIT_SINGLETHREADED);
    if (Failed(initialise))
    {
        return 1;
    }

    ComPtr<IClipboardStatics> clipboard;
    HRESULT hr2 = GetActivationFactory(HStringReference(RuntimeClass_Windows_ApplicationModel_DataTransfer_Clipboard).Get(),&clipboard);

    ComPtr<IDataPackage> dataPackage;
    hr2 = ActivateInstance(HStringReference(RuntimeClass_Windows_ApplicationModel_DataTransfer_DataPackage).Get(),&dataPackage);

    hr2 = dataPackage.Get()->SetText(HStringReference(L"Testing 1 2 3 4").Get());

    hr2 = clipboard.Get()->SetContent(dataPackage.Get());

然而，事实证明添加位图要困难得多。我花了很多时间查看源代码、阅读文档和编写测试代码，最终得到以下结果（注意我从 HD 读取了一个 BMP 文件用于测试目的）：

    HRESULT hr2;

    ComPtr<IDataWriter> imageDataWriter;
    ComPtr<IRandomAccessstream> imagestream;
    ComPtr<IRandomAccessstreamReference> imagestreamReference;
 
    RoInitializeWrapper initialise(RO_INIT_SINGLETHREADED);
    if (Failed(initialise))
    {
         return 1;
    }

    hr2 = ActivateInstance(HStringReference(RuntimeClass_Windows_Storage_Streams_InMemoryRandomAccessstream).Get(),imagestream.GetAddressOf());


    ComPtr<IoUtputStream> outputStream;
    hr2 = imagestream.As(&outputStream);

    ComPtr<IDataWriterFactory> dataWriterFactory;
    hr2 = GetActivationFactory(HStringReference(RuntimeClass_Windows_Storage_Streams_DataWriter).Get(),dataWriterFactory.GetAddressOf());

    hr2 = dataWriterFactory->CreateDataWriter(outputStream.Get(),imageDataWriter.GetAddressOf());

    BYTE* data = nullptr;

    std::streampos size;
    std::ifstream in(L"c:\\temp\\background.bmp",std::ios::in|std::ios::binary|std::ios::ate);
    if (in.is_open())
    {
        size = in.tellg();

        data = new BYTE[size];
        in.seekg(0,std::ios::beg);
        in.read((char*) data,size);
        in.close();
    }

    hr2 = imageDataWriter->WriteBytes(size,data);

    ComPtr<IDataPackage> dataPackage;
    hr2 = ActivateInstance(HStringReference(RuntimeClass_Windows_ApplicationModel_DataTransfer_DataPackage).Get(),&dataPackage);

    ComPtr<IRandomAccessstreamReferenceStatics> streamRefFactory;
    hr2 = GetActivationFactory(HStringReference(RuntimeClass_Windows_Storage_Streams_RandomAccessstreamReference).Get(),streamRefFactory.GetAddressOf());

    hr2 = streamRefFactory->CreateFromStream(imagestream.Get(),imagestreamReference.GetAddressOf());

    hr2 = dataPackage.Get()->SetBitmap(imagestreamReference.Get());

    hr2 = dataPackage->put_RequestedOperation(DataPackageOperation::DataPackageOperation_copy);

    ComPtr<IClipboardStatics> clipboard;
    hr2 = GetActivationFactory(HStringReference(RuntimeClass_Windows_ApplicationModel_DataTransfer_Clipboard).Get(),&clipboard);

    hr2 = clipboard.Get()->SetContent(dataPackage.Get());

    clipboard->Flush();

所有 WRL 函数都返回 S_OK，但实际上剪贴板中没有任何内容。当 IRandomAccessstreamReference 超出范围时，我确实收到了异常，因此这可能是一个线索。

任何关于我做错了什么的线索？这是我第一次使用 Windows 运行时，老实说，我发现使用它非常令人沮丧。