Insert picture in TRichEdit from code

[aehimself 396]

Hello,

 

Due to various reasons I'm experimenting with Delphi's TRichEdit component. I looked into the demo and quickly learned the basics but I didn't find any way to insert a picture.

My searches lead to two solutions:

- LINK. With a RichOle.pas file create an object from the image and insert it into the RichEdit using OLE. This method worked, but it embeds it instead of inserting (image is not shown, only an icon and the file name. Picture opens correctly when double-clicked)

- LINK. Load the bitmap and convert it into rich edit compatible code. Insert this code using EM_STREAMIN. This method did absolutely nothing

 

Another way (which probably works) is to copy the picture to the clipboard and paste it's contents into the RichEdit but this just feels way too hacky.

 

The question is, how to insert a picture in a TRichEdit the most elegant way? I'm attempting on Delphi 10.4.1 / 10.4.2 / 11.1.

 

Thanks!

[Dave Novo 51]

The TRichview forums are excellent. You should post your questions there. Firstly, I am sure that question is answered there if you search, and if not, Sergey (the main developer) will give you a detailed answer.

 

i.e.

https://www.trichview.com/forums/viewtopic.php?p=35009&hilit=insert+picture#p35009

[Remy Lebeau 1394]

1 hour ago, aehimself said:

- LINK. With a RichOle.pas file create an object from the image and insert it into the RichEdit using OLE. This method worked, but it embeds it instead of inserting (image is not shown, only an icon and the file name. Picture opens correctly when double-clicked)

IRichEditOle is the correct way to insert pictures into a RichEdit.  The code should have embedded the image's data directly into the RichEdit's content, not create a link to an external file that is launched separately.  If you can wrap the image in an IDataObject instead of an IOleObject, then you might try using IRichEditOle.ImportDataObject() instead of IRichEditOle.InsertObject().

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- LINK. Load the bitmap and convert it into rich edit compatible code. Insert this code using EM_STREAMIN. This method did absolutely nothing

I think that approach should work, provided the generated RTF content is accurate.  However, in Delphi 2009+, string is UnicodeString, so the BitmapToRTF() function would need to be changed to use AnsiString or TBytes internally when preparing the RTF, since RTF is an 8-bit format. And also, since the TStringStream used to stream the RTF into the RichEdit would be holding Unicode characters, you probably need to include the SF_UNICODE flag when sending the EM_STREAMIN message.  Otherwise, use a TMemoryStream instead to hold 8bit data instead of 16bit data. Also, there are 2 memory leaks in that code's Button1Click() method,

Quote

The question is, how to insert a picture in a TRichEdit the most elegant way?

Unfortunately, there is no "elegant" way, since Microsoft does not provide an "easy" API to handle this task.

 

Edited July 13, 2022 by Remy Lebeau

[FreeDelphiPascal 19]

This free lib has support for inserting images in RichEdit:

http://www.micrel.cz/RxLib/dfiles.htm