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version 2003
PA_GetPictureHandleField (tNum; fNum; info) 
PA_Handle
| Parameter | Type | Description | |
| tNum | short | | Table number of the field to access |
| fNum | short | | Field number of the field to access |
| info | PA_PictureInfo* |  | Pointer to picture info |
| Function result | PA_Handle | | Handle to the picture |
Description
The routine PA_GetPictureHandleField returns a handle to the picture data of the field number fNum of the current record of table number tNum. It returns the picture info used when the picture is displayed in the background in *info.
If the field is not a picture field, the routine leaves info unchanged, returns 0 and set an error code in PA_GetLastError.
WARNING
The handle belongs to 4th Dimension. Never dispose of it.
To get a copy of the picture data, use PA_GetPictureField. It is only really useful for getting the Handle for saving memory, especially if the plug-in only wants to view the picture as "read-only".
Example
Draw a picture on Macintosh (and Windows + Mac2Win) : the received handle is a regular PicHandle.
void DrawPictureField( short tNum, short fNum, Rect *r )
{
PA_Handle h =0L;
PA_PictureInfo info;
h = PA_GetPictureHandleField( tNum, fNum, r, &info );
DrawPicture( (PicHandle) h, &r );
// Do NOT dispose the picture here, it stills belongs to 4D
}
See Also
PA_GetPictureField, PA_SetPictureField, PA_SetPictureHandleField.
Error Handling
Use PA_GetLastError to see if an error occurred (eER_InvalidFileNumber, eER_InvalidFieldNumber).
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