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WMIsAvailableOffline function (wmsdkvalidate.h)

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[The feature associated with this page, Windows Media Format 11 SDK, is a legacy feature. It has been superseded by Source Reader and Sink Writer. Source Reader and Sink Writer have been optimized for Windows 10 and Windows 11. Microsoft strongly recommends that new code use Source Reader and Sink Writer instead of Windows Media Format 11 SDK, when possible. Microsoft suggests that existing code that uses the legacy APIs be rewritten to use the new APIs if possible.]

The WMIsAvailableOffline function verifies that an ASF file can be played from a cached copy. If a user plays a file from a network location, part or all of the file may be stored in a cache. If that cached copy exists on the local machine, the user may be able to play the file without being connected to the network.

Syntax

HRESULT WMIsAvailableOffline(
  [in]  LPCWSTR pwszURL,
  [in]  LPCWSTR pwszLanguage,
  [out] BOOL    *pfIsAvailableOffline
);

Parameters

[in] pwszURL

Wide-character null-terminated string containing the URL of the file to be checked.

[in] pwszLanguage

Wide-character null-terminated string containing the RFC 1766-compliant language ID specifying which language is desired for playback. This value is only important for files that contain language-based mutual exclusion.

Set to NULL if all languages are acceptable.

[out] pfIsAvailableOffline

Pointer to a Boolean value that is set to True if the file is available offline.

Return value

The function returns an HRESULT. Possible values include, but are not limited to, those in the following table.

Return code Description
S_OK
 The function succeeded.
E_INVALIDARG
 One or both of the input parameters are NULL.

Requirements

Requirement Value
Minimum supported client Windows 2000 Professional [desktop apps only],Windows Media Format 9 Series SDK, or later versions of the SDK
Minimum supported server Windows 2000 Server [desktop apps only]
Target Platform Windows
Header wmsdkvalidate.h (include Wmsdkidl.h)
Library Wmvcore.lib
DLL Wmvcore.dll

See also

Functions