Bo Durban - MoxieData Blog - Insert Images into an RTF control using GDIPlusX

Original post by Bo Durban, replicated here because the original blog http://blog.moxiedata.com is not responding.
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Insert Images into an RTF control using GDIPlusX

The RichText control that ships with VFP is very useful for providing a formatted text edit box. While this control does support the displaying of images, there is nothing built in to the control that allows you to insert an image. I have included a function below that will allow you insert an image into the RichText control at the current cursor position.

Just specify the object reference to the RTF control and the fullpath of the image you want to insert. The image can be in any format supported by the GDIPlus library (BMP, JPEG, GIF, TIFF, EMF, PNG, etc...). You can also optionally specify the Width and Height you would like the image to be rendered.

This function requires the GDIPlusX library which can be downloaded from the VFPX  GDIPlusX project at Github.

***********************************************************
* Function: InsertRTFImage
* Author: Bo Durban
*
* Inserts an image into an RTF control at the current cusor position
*
* Parameters:
*   toRTF - specifies an object reference to the RTF control
*   tcImage - secifies the image to insert into the RTF
*   tnWidth - Optional - Specifies the width to use for the image
*   tnHeight - Optional - Specifies the height to use for the image
***********************************************************
FUNCTION InsertRTFImage(toRTF, tcImage, tnWidth, tnHeight)
   LOCAL lcRTF, lcPict, lqData
   LOCAL loImg AS xfcImage
   LOCAL loGfx AS xfcGraphics
   LOCAL loEMF AS xfcMetaFile
   LOCAL lhDC, lhEMF, lnWMFLen
  
   DECLARE Long GetDC IN WIN32API Long
   DECLARE Long ReleaseDC IN WIN32API Long, Long
   DECLARE Long DeleteEnhMetaFile IN WIN32API Long
   DECLARE Long GdipEmfToWmfBits IN GDIPLUS.DLL ;
         Long hemf, Long cbData16, String @pData16, ;
         Integer iMapMode, Integer eFlags
  
   ** Make sure we have initialized the GDIPlusX library
   ** http://www.codeplex.com/VFPX/Wiki/View.aspx?title=GDIPlusX
   DO System.App
  
   lcPict = ""
   WITH _SCREEN.System.Drawing
      loImg = .Image.FromFile(tcImage)
      IF loImg.GetLastStatus() <> 0
         ERROR "Could not open file: "+tcImage
      ELSE
         ** If we didn't specify a width, use the image's width and height
         IF EMPTY(tnWidth)
            tnWidth = loImg.Width
            tnHeight = loImg.Height
         ENDIF
         ** Get the default screen HDC as a reference
         lhDC = GetDC(0)
         ** Create a new metafile
         loEMF = .Imaging.MetaFile.New(lhDC, ;
            .Rectangle.New(0,0,tnWidth,tnHeight), ;
            .Imaging.MetafileFrameUnit.Pixel, ;
            .Imaging.MetafileType.Emf)
         ** We are done with the HDC reference, release it
         ReleaseDC(lhDC, 0)
         ** Get a graphics context for the metafile so we can draw to it
         loGfx = .Graphics.FromImage(loEMF)
         loGFX.SmoothingMode = .Drawing2D.SmoothingMode.HighQuality
         loGFX.InterpolationMode = .Drawing2D.InterpolationMode.HighQualityBicubic
         ** Draw the image
         loGfx.DrawImage(loImg, 0, 0, tnWidth, tnHeight)
         loGfx = NULL
        
         ** Convert the Metafile to a "Windows Metafile".
         ** This is the best format for the RTF control.
         lhEMF = loEMF.GetHenhmetafile()
         lnWMFLen = GdipEmfToWmfBits(lhEMF, 0, NULL, 2, 0)
         lqData = REPLICATE(0h00,lnWMFLen)
         GdipEmfToWmfBits(lhEMF, lnWMFLen, @lqData, 2, 0)
         DeleteEnhMetaFile(lhemf)
         loImg = NULL
        
         ** This is the RTF tags for the image
         lcPict = [{\pict\wmetafile8]+;
                  [\picwgoal]+ALLTRIM(STR(tnWidth*15))+;
                  [\pichgoal]+ALLTRIM(STR(tnHeight*15))+;
                  CHR(13)+CHR(10)+;
                  STRCONV(lqData, 15)+;
                  CHR(13)+CHR(10)+[}]
      ENDIF
   ENDWITH
  
   ** Stuff the image into the RTF control
   toRTF.SelRTF = [{\rtf1\ansi\ansicpg1252\deff0\deflang1033\uc1 ]+lcPict+[}]

   RETURN
ENDFUNC