C# VSTO Outlook Outgoing Message Hyperlink

Question

I am creating a C# VSTO add-in for Outlook 2010. I am attempting to generate a hyperlink at the insertion point of the active outgoing message that is being worked on (the hyperlink is inserted via a button on the message window ribbon). All other functions of the add-in (ribbon button, accessing the ActiveInspector().CurrentItem , etc.) work fine. I am working with this code:

object linktext = txtDisplayText.Text;
object result = "MY URL";
object missObj = Type.Missing;

Outlook.MailItem currentMessage = 
     Globals.ThisAddIn.Application.ActiveInspector().CurrentItem;
Word.Document doc = currentMessage.GetInspector.WordEditor;
object oRange = doc.Windows[1].Selection;
doc.Application.Selection.Hyperlinks.Add
    (oRange, ref result, ref missObj, ref missObj, ref linktext, ref missObj);

When I run this code I get the message "Command failed." I suspect I am missing something either in regards to how Outlook uses Microsoft Word's editor for Outlook messages or in the way I have specified the selection object in oRange . Any help is very much appreciated.

Answer 1

This issue was indeed caused by the way the selection was defined for the Hyperlinks.Add command. Instead of an object type, the selection needed to be typed as a Microsoft Word Selection (due to the fact that Outlook uses Word as its editor):

Word.Selection objSel = doc.Windows[1].Selection;

So to insert a hyperlink at the insertion point of an Outlook message during composition, the code has using statements for both Word and Outlook:

using Outlook = Microsoft.Office.Interop.Outlook;
using Word = Microsoft.Office.Interop.Word;

And then this code:

object linktext = txtDisplayText.Text;
object result = "MY URL";
object missObj = Type.Missing;

Outlook.MailItem currentMessage = 
     Globals.ThisAddIn.Application.ActiveInspector().CurrentItem;
Word.Document doc = currentMessage.GetInspector.WordEditor;
Word.Selection objSel = doc.Windows[1].Selection;
doc.Hyperlinks.Add
     (objSel.Range, ref result, ref missObj, ref missObj, ref linktext, ref missObj);

Two other adjustments are worth noting. Because a Word.Selection type was used for the anchor of the hyperlink, the Hyperlinks.Add command needed to be changed from doc.Application.Selection.Hyperlinks.Add to doc.Hyperlinks.Add . And because Outlook uses Microsoft's Word editor, the anchor for doc.Hyperlinks.Add used a range: objSel.Range .

Answer 2

Use the HTMLBody property of the MailItem class for modifying the message body (inserting a hyperlink) in the ItemSend event handler instead. You need to find the place where to paste a hyperlink <a href=.../> , modify the HTML well formed string and assign it back.