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IWMDMDevice2::GetStorage

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The GetStorage method searches the immediate children of the root storage for a storage with the given name.

Syntax

HRESULT GetStorage(LPCWSTRpszStorageName,IWMDMStorage**ppStorage);

Parameters

pszStorageName

[in]  Pointer to a null-terminated string specifying the name of the storage to find. This parameter does not support wildcard characters.

ppStorage

[out]  Pointer to the IWMDMStorage interface of the storage specified by the pszStorageName parameter. The caller must release this interface when done with it.

Return Values

The method returns an HRESULT. All the interface methods in Windows Media Device Manager can return any of the following classes of error codes:

  • Standard COM error codes
  • Windows error codes converted to HRESULT values
  • Windows Media Device Manager error codes

For an extenstive list of possible error codes, see Error Codes.

Possible values include, but are not limited to, those in the following table.

Return code Description
S_OK The method succeeded.
S_FALSE The storage cannot be found.

Remarks

This function is not recursive; it only searches the immediate children of the device root storage. For a recursive search version of this function, use IWMDMDevice3::FindStorage.

Example Code

The following C++ function searches for a storage recursively. It uses GetStorage to search the immediate children; if the requested storage is not found, it then loops through all the children and recursively searches folders.

HRESULT myFindStorageRecursively(LPCWSTR storageName, IWMDMStorage* pCurrentStorage, IWMDMStorage** ppFoundStorage)
{
    HRESULT hr = S_OK;

    // Start with a quick check of all storages inside the storage.
    // If we found it, stop now and return.
    CComQIPtr<IWMDMStorage2> pStorage2(pCurrentStorage);
    hr = pStorage2->GetStorage(storageName, ppFoundStorage);
    if (*ppFoundStorage != NULL)
        return hr;

    //
    // Otherwise, enumerate through and dive into all child folders.
    //

    // First get enumerator.
    CComPtr<IWMDMEnumStorage> pEnumStorage;
    hr = pCurrentStorage->EnumStorage(&pEnumStorage);
    if (hr != S_OK && pEnumStorage != NULL)
        return hr;

    // Now enumerate all folders until found the right item, or out of folders.
    CComPtr<IWMDMStorage> pThisStorage;
    DWORD numRetrieved = 0;
    DWORD attr = 0;
    while(pEnumStorage->Next(1, &pThisStorage, &numRetrieved) == S_OK)
    {
        pThisStorage->GetAttributes(&attr, NULL);
        if (attr & WMDM_FILE_ATTR_FOLDER)
        {
            hr = myFindStorageRecursively(storageName, pThisStorage, ppFoundStorage);
            if (*ppFoundStorage != NULL)
                return hr;
        }
        pThisStorage.Release();
    }

    return hr;
}

Requirements

Header: Defined in mswmdm.h.

Library: mssachlp.lib

See Also