Here's a simple method to programmatically insert an image into a RichTextBox control, by copying it into the clipboard and then pasting it into the control:
Private Declare Function SendMessage Lib "user32" Alias "SendMessageA" (ByVal _
hwnd As Long, ByVal wMsg As Long, ByVal wParam As Long, _
lParam As Any) As Long
Private Const WM_PASTE = &H302
Sub InsertPictureInRichTextBox(RTB As RichTextBox, Picture As StdPicture)
' copy into the clipboard
' Copy the picture into the clipboard.
Clipboard.Clear
Clipboard.SetData Picture
' paste into the RichTextBox control
SendMessage RTB.hwnd, WM_PASTE, 0, 0
End Sub
You can load the picture from another control (a PictureBox, for example), or directly from a file using the LoadPicture function:
InsertPictureInRichTextBox RichTextBox1, LoadPicture("c:\winnt\coffee bean.bmp")