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IThumbnailCache::GetThumbnailByID method (thumbcache.h)

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Gets a thumbnail from the thumbnail cache, given its ID.

Syntax

HRESULT GetThumbnailByID(
  [in]            WTS_THUMBNAILID thumbnailID,
  [in]            UINT            cxyRequestedThumbSize,
  [out, optional] ISharedBitmap   **ppvThumb,
  [out, optional] WTS_CACHEFLAGS  *pOutFlags
);

Parameters

[in] thumbnailID

Type: WTS_THUMBNAILID

The ID of the thumbnail to retrieve. The ID is obtained by calling GetThumbnail.

[in] cxyRequestedThumbSize

Type: UINT

The requested thumbnail size in pixels. This value cannot be larger than 1024.

[out, optional] ppvThumb

Type: ISharedBitmap**

The address of a ISharedBitmap interface pointer that, when this method returns successfully, receives the object for accessing the requested thumbnail. This parameter can be NULL.

[out, optional] pOutFlags

Type: WTS_CACHEFLAGS*

A pointer to a value that, when this method returns successfully, receives a combination of the following flags. This value can be set to NULL if this information is not needed.

WTS_DEFAULT (0x00000000)

0x00000000.

WTS_LOWQUALITY (0x00000001)

0x00000001. Set when the returned bitmap dimensions are less than cxyRequestedThumbSize.

WTS_CACHED (0x00000002)

0x00000002. Set when the returned image is in the cache.

Return value

Type: HRESULT

Returns S_OK if successful, or an error value otherwise, including the following:

Return code Description
E_INVALIDARG
 A parameter is invalid.
WTS_E_FAILEDEXTRACTION
 The Shell item does not support thumbnail extraction. For example, .exe or .lnk items.
WTS_E_EXTRACTIONTIMEDOUT
 The extraction took longer than the maximum allowable time. The extraction was not completed.
WTS_E_SURROGATEUNAVAILABLE
 A surrogate process was not available to be used for the extraction process.
WTS_E_FASTEXTRACTIONNOTSUPPORTED
 The WTS_FASTEXTRACT flag was set, but fast extraction is not available.

Remarks

This method is typically called after GetThumbnail has already been called to retrieve the thumbnail ID.

Requirements

Requirement Value
Minimum supported client Windows Vista [desktop apps only]
Minimum supported server Windows Server 2008 [desktop apps only]
Target Platform Windows
Header thumbcache.h