wpclsQueryInstanceType
This method is called to allow the class object to specify the file types for instances of its class.
Syntax
_wpclsQueryInstanceType(somSelf)
Parameters
- somSelf (M_WPFileSystem *) - input
- Pointer to the WPFileSystem class object.
- psuccess (PSZ) - returns
- Success indicator. NULL Error occurred. Other A pointer to a string containing file types. This string can contain several file types separated by commas. For example: 'Plain Text,C Code'.
Returns
- psuccess (PSZ) - returns
- Success indicator. NULL Error occurred. Other A pointer to a string containing file types. This string can contain several file types separated by commas. For example: 'Plain Text,C Code'.
Remarks
It is recommended that object classes define their own special type strings.
How to Override
This method should be overridden in order to automatically designate file objects as instances of this class. The value returned by the override method will replace the current type string which is used to designate instances. If the parent method is called, it should be called first.
Usage
This method can be called at any time in order to determine which file types are used to determine instances of this class.
Example Code
Declaration:
#define INCL_WINWORKPLACE #include <os2.h> M_WPFileSystem *somSelf; /* Pointer to the WPFileSystem class object. */ PSZ psuccess; /* Success indicator. */ psuccess = _wpclsQueryInstanceType(somSelf);
This example associates two file types as being associated with the Picture object.
SOM_Scope PSZ SOMLINK PictureM_wpclsQueryInstanceType(M_Picture *somSelf)
{
/* M_PictureData *somThis = M_PictureGetData(somSelf); */
M_PictureMethodDebug('M_Picture','PictureM_wpclsQueryInstanceType');
/* return (parent_wpclsQueryInstanceType(somSelf)); no call to parent */
return ( 'JPG File,GIF File' );
}