Comment example for C++ Builder

This example does the following:

1.	Loads an image from a TIFF file.
2.	Updates the current comment array by reading comments from the file.
3.	Modifies one of the comments.
4.	Modifies and saves the file.
5.	Reads the comment that was saved, and displays it in a message box.
	This example handles only string comments. For more complex comments, refer to Exif Examples.

void __fastcall TForm1::ReadComment1Click(TObject *Sender)
{
   Variant Empty; /* For clearing comments */
   AnsiString MyCommentText; /* String for CMNT_SZDESC */
   AnsiString NewCommentText; /* String for CMNT_SZDESC that we read */
   AnsiString FilePath; /* File to be updated */
   int i; /* Counter */

   /* Specify the file that we will update. */
   FilePath = "c:\\ testcmt.tif";
   /* Specify the Empty variant for clearing comments. */
   VarClear(Empty);
   /* Get all of the current comments from the file. */
   /* Temporarily disable method errors so that we do not fail when comments are missing. */
   LeadImage1->EnableMethodErrors = False;
   for (i = 0; i <= CMNT_LAST; i++)
   {
      LeadImage1->Comment[i] = Empty;
      LeadImage1->Comment[i] = LeadImage1->ReadComment(FilePath, 0, i);
   }
   LeadImage1->EnableMethodErrors = True;
   /* Load and modify the image. */
   LeadImage1->Load(FilePath, 0, 0, 1);
   LeadImage1->Reverse();
   /* Update the CMNT_SZDESC comment. */
   MyCommentText = "\nThis image has been reversed.";
   LeadImage1->Comment[CMNT_SZDESC] = LeadImage1->Comment[CMNT_SZDESC] + MyCommentText;
   /* Save the file and read the comment that we saved. */
   LeadImage1->Save(FilePath, FILE_TIF, LeadImage1->BitmapBits, 0, SAVE_OVERWRITE);
   NewCommentText = LeadImage1->ReadComment(FilePath, 0, CMNT_SZDESC);
   /* Display the message. */
   Application->MessageBox(NewCommentText.c_str(), "File Comments", MB_OK);
   /* Clear the comments from memory. */
   for (i = 0; i <= CMNT_LAST; i++) LeadImage1->Comment[i] = Empty;
}