IAttachmentExecute interface (shobjidl_core.h)

Exposes methods that work with client applications to present a user environment that provides safe download and exchange of files through email and messaging attachments.

Inheritance

The IAttachmentExecute interface inherits from the IUnknown interface. IAttachmentExecute also has these types of members:

Methods

The IAttachmentExecute interface has these methods.

Remarks

This interface assumes the following:

• The client has policies or settings for attachment support and behavior.
• The client interacts with the user.

Here is an example of how an email client might use IAttachmentExecute.

// CClientAttachmentInfo, defined by the client, implements all the
// necessary client functionality concerning attachments. 
class CClientAttachmentInfo;  

// Creates an instance of IAttachmentExecute
HRESULT CreateAttachmentServices(IAttachmentExecute **ppae)
{
    // Assume that CoInitialize has already been called for this thread.
    HRESULT hr = CoCreateInstance(CLSID_AttachmentServices, 
                                  NULL, 
                                  CLSCTX_INPROC_SERVER, 
                                  IID_IAttachmentExecute, 
                                  (void**)&pAttachExec);

    if (SUCCEEDED(hr))
    {
        // Set the client's GUID.

        // UUID_ClientID should be created using uuidgen.exe and 
        // defined internally.
        (*ppae)->SetClientGuid(UUID_ClientID);
        
        // You also could call SetClientTitle at this point, but it is
        // not required.
    }
    return hr;
}

BOOL IsAttachmentBlocked(CClientAttachmentInfo *pinfo)
{
    // Assume that a client function has copied the file from the mail store 
    // into a temporary file.
    PWSTR pszFileName;

    // GetFileName is a method in this class for which we do not provide
    // an implementation here.
    HRESULT hr = pinfo->GetFileName(&pszFileName);
    if (SUCCEEDED(hr))
    {
        IAttachmentExecute *pExecute;

        hr = CreateAttachmentServices(&pExecute);
        if (SUCCEEDED(hr))
        {
            hr = pExecute->SetFileName(pszFileName);

            // Do not call SetLocalPath since we do not have the local path yet.
            // Do not call SetSource since email sources are not verifiable.
            // Do not call SetReferrer since we do not have a better zone 
            // than the default (Restricted sites).

            // Check for a policy regarding the file.
            if (SUCCEEDED(hr))
            {
                hr = pExecute->CheckPolicy();
            }
            pExecute->Release();
        }
        LocalFree(pszFileName);
    }
    return FAILED(hr);
}
    
HRESULT OnDoubleClickAttachment(HWND hwnd, CClientAttachmentInfo *pinfo)
{
    // Assume that a client function has copied the file from the mail store 
    // into a temporary file.
    PWSTR pszTempFile;

    // CopyToTempFile is a method in this class for which we do not provide
    // an implementation here.
    HRESULT hr = pinfo->CopyToTempFile(&pszTempFile);
    if (SUCCEEDED(hr))
    {
        IAttachmentExecute *pExecute;

        hr = CreateAttachmentServices(&pExecute);
        if (SUCCEEDED(hr))
        {
            hr = pExecute->SetLocalPath(pszTempFile);

            // Do not call SetFileName since we already have the local path.
            // Do not call SetSource since email sources are not verifiable.
            // Do not call SetReferrer since we do not have a better zone 
            // than the default (Restricted sites).

            if (SUCCEEDED(hr))
            {
                hr = pExecute->Execute(hwnd, NULL, NULL);
            }
            pExecute->Release();
        }
        LocalFree(pszTempFile);
    }
    return hr;
}

HRESULT OnSaveAttachment(HWND hwnd, CClientAttachmentInfo *pinfo)
{
    // Assume that a client function has copied the file from the mail store 
    // into a location selected by the user.
    PWSTR pszUserFile;

    // CopyToUserFile is a method in this class for which we do not provide
    // an implementation here.
    HRESULT hr = pinfo->CopyToUserFile(hwnd, &pszUserFile);
    if (SUCCEEDED(hr))
    {
        IAttachmentExecute *pExecute;

        hr = CreateAttachmentServices(&pExecute);
        if (SUCCEEDED(hr))
        {
            hr = pExecute->SetLocalPath(pszTempFile);

            // Do not call SetFileName since we have the local path.
            // Do not call SetSource since email sources are not verifiable.
            // Do not call SetReferrer since we do not have a better zone 
            // than the default (Restricted sites).

            if (SUCCEEDED(hr))
            {
                hr = pExecute->Save();
            }
            pExecute->Release();
        }
        LocalFree(pszUserFile);
    }
    return hr;
}

Requirements