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L_AnnGetUserData

Summary

Gets the user-defined data of one or more annotation objects.

Syntax

#include "l_bitmap.h"

L_LTANN_API L_INT L_AnnGetUserData(hObject, pUserData, puUserDataSize)

Parameters

HANNOBJECT hObject

Handle to the annotation object.

L_UCHAR *pUserData

Address that binary data is read into. Can be NULL.

L_UINT *puUserDataSize

Address of variable to be updated with the length (in bytes) of the user data

Returns

Value	Meaning
SUCCESS	The function was successful.
< 1	An error occurred. Refer to Return Codes.

Comments

Use this function to get the associated user-defined data of an annotation object.

When getting the user-defined data, call this function twice: one time with pUserData set to NULL to get the length of the data, and another time to get the actual data.

HANNOBJECT hObject;   
L_UCHAR *pUserData;   
L_UINT uUserDataSize;   
// Assume hObject is a valid annotation object   
L_AnnGetUserData(hObject, NULL, &uUserDataSize);   
pUserData = (L_UCHAR *)malloc(uUserDataSize);   
L_AnnGetUserData(hObject, pUserData, &uUserDataSize);

User data can be binary or text data, and can be any length. When the annotation object is copied, and the user data is also copied. When saving the annotation (L_AnnSave, L_AnnSaveMemory, L_AnnSaveOffset), the user data is saved.

Required DLLs and Libraries

LTANN
For a listing of the exact DLLs and Libraries needed, based on the toolkit version, refer to Files To Be Included With Your Application.

Platforms

Win32, x64.

Example

This sample loads/saves the contents of a BITMAPHANDLE from/to user data of an annotation object
Call the sample once with bSave set to L_TRUE, then call it again with bSave set to L_FALSE to
load the saved user data as a BITMAPHANDLE
hObject -- the annotation object
pBitmap -- the bitmap that is loaded/saved
bLoad -- L_TRUE means load from the annotation object, L_FALSE means save to the annotation object

L_INT AnnGetUserDataExample(HANNOBJECT hObject, pBITMAPHANDLE pBitmap, L_BOOL bSave) 
{ 
   L_INT       nRet; 
   L_HGLOBAL   hGlobal = NULL; 
   L_SIZE_T    zUserDataSize = 0; 
   L_UCHAR*    pUserData; 
 
   if (!pBitmap || !hObject) 
      return 0; 
 
   if (bSave) // saving 
   { 
      nRet = L_SaveBitmapMemory(&hGlobal, pBitmap, FILE_BMP, 24, 0, &zUserDataSize, NULL); 
      if (nRet != SUCCESS) 
         return nRet; 
 
      pUserData = (L_UCHAR*)GlobalLock(hGlobal); 
 
      nRet = L_AnnSetUserData(hObject, pUserData, (L_UINT)zUserDataSize, ANNFLAG_NOINVALIDATE); 
      if (nRet != SUCCESS) 
         return nRet; 
 
      GlobalUnlock(hGlobal); 
      GlobalFree(hGlobal); 
   } 
   else // loading 
   { 
      // Load  
      nRet = L_AnnGetUserData(hObject, NULL, (L_UINT*)&zUserDataSize); 
      if (nRet != SUCCESS) 
         return nRet; 
 
      pUserData = (L_UCHAR*)malloc(zUserDataSize); 
      nRet = L_AnnGetUserData(hObject, pUserData, (L_UINT*)&zUserDataSize); 
      if (nRet != SUCCESS) 
         return nRet; 
 
      nRet = L_LoadBitmapMemory(pUserData, pBitmap, sizeof(BITMAPHANDLE), 0, ORDER_BGRORGRAY, zUserDataSize, NULL, NULL); 
      if (nRet != SUCCESS) 
         return nRet; 
 
      free(pUserData); 
   } 
 
   return SUCCESS; 
}