IMediaParamInfo::GetParamText method (medparam.h)
[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 It has been superseded by MediaPlayer, IMFMediaEngine, and Audio/Video Capture in Media Foundation.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.]
The GetParamText
method retrieves a series of text strings that describe the parameter.
Syntax
HRESULT GetParamText(
[in] DWORD dwParamIndex,
[out] WCHAR **ppwchText
);
Parameters
[in] dwParamIndex
Zero-based index of the parameter.
[out] ppwchText
Address of a variable that receives a pointer to a series of Unicodeā¢ strings.
Return value
Returns an HRESULT value. Possible values include the following.
Return code | Description |
---|---|
|
Index out of range. |
|
NULL pointer argument. |
|
Success. |
Remarks
If the method succeeds, *ppwchText points to a string with the following format:
Name\0Unit\0Enum1\0Enum2\0...EnumN\0\0
where
- Name is the name of the parameter.
- Unit is the name of the units; for example, milliseconds.
- Enum1 through
- EnumN are descriptive names for the parameter's enumerated values. (Applies only to parameters of type MPT_ENUM.)
The object uses the CoTaskMemAlloc function to allocate memory for the string. After you call this method, call CoTaskMemFree to free the buffer.
Requirements
Requirement | Value |
---|---|
Target Platform | Windows |
Header | medparam.h |
Library | Dmoguids.lib |