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IMediaLocator::FindMediaFile method

[The feature associated with this page, DirectShow, is a legacy feature. It has been superseded by MediaPlayer, IMFMediaEngine, and Audio/Video Capture in Media Foundation. Those features have been optimized for Windows 10 and Windows 11. Microsoft strongly recommends that new code use MediaPlayer, IMFMediaEngine and Audio/Video Capture in Media Foundation instead of DirectShow, when possible. Microsoft suggests that existing code that uses the legacy APIs be rewritten to use the new APIs if possible.]

Note

[Deprecated. This API may be removed from future releases of Windows.]

 

The FindMediaFile method searches for a file and, if successful, retrieves the path to the file.

Syntax

HRESULT FindMediaFile(
   BSTR Input,
   BSTR FilterString,
   BSTR *pOutput,
   long Flags
);

Parameters

Input

File name, including path, where the file was last known to reside. For source objects in the timeline, use the current media name.

FilterString

A BSTR containing pairs of filter strings, formatted as required by the lpstrFilter member of the OPENFILENAME structure. The media locator uses this filter if it displays a File Open dialog box. The value can be NULL if the Flags parameter does not include the SFN_VALIDATEF_POPUP flag.

pOutput

Pointer to a variable that receives the actual path to the file, if it differs from the value contained in Input and if the method successfully locates the file.

Flags

Bitwise combination of zero or more flags. For a list of possible flags, see File Name Validation Flags.

Return value

If this method succeeds, it returns S_OK. Otherwise, it returns an HRESULT error code.

Remarks

The filter string for the File Open dialog, which is specified by the FilterString parameter, contains internal Null characters. For example, Video\0*.avi\0\0 is a valid filter string. You cannot use the SysAllocStr function to allocate the BSTR, because that function expects a Null-terminated string and will truncate the string at the first Null character. Therefore, use a function such as SysAllocStringLen, which includes an explicit parameter for the length:

BSTR filter = SysAllocStringLen(L"Video\0*.avi\0", 12);
// Note: SysAllocStringLen appends an additional '\0' to the string.

If the user cancels the File Open dialog, the method returns E_FAIL.

The method allocates memory for the BSTR in pOutput. The application must call SysFreeString to free the memory.

Note

The header file Qedit.h is not compatible with Direct3D headers later than version 7.

 

Note

To obtain Qedit.h, download the Microsoft Windows SDK Update for Windows Vista and .NET Framework 3.0. Qedit.h is not available in the Microsoft Windows SDK for Windows 7 and .NET Framework 3.5 Service Pack 1.

 

Requirements

Requirement Value
Header
Qedit.h
Library
Strmiids.lib

See also

IMediaLocator Interface

Error and Success Codes