How do I make links activatable in rtb?.

Send an EM_AUTOURLDETECT message.

Use the SendMessage function to send a message to it, and the message that is being sent should be EM_AUTOURLDETECT.  Understand!?

Well heres a way to make it recognize the link from the rest of the text... but as for making it actually go to the page i havent gotten that far yet :| [code]
Private Sub highlightHyperlink()
On Error Resume Next
Dim pos As Long
Dim posEnd As Long
Dim char As String
Dim link As String
pos = InStr(1, LCase$(rtb.Text), "mailto:")

Do While pos > 0

For posEnd = pos To Len(rtb.Text)
char = Mid$(rtb.Text, posEnd, 1)
If char = Chr$(32) Or char = Chr$(10) Or char = Chr$(13) Then Exit _
For
Next posEnd
link = Mid$(rtb.Text, pos, posEnd - pos)
char = Right$(link, 1)

Do While char = "." Or char = "," Or char = "!" Or char = "?" Or _
Len(char) <> 1
link = Left$(link, Len(link) - 1)
char = Right$(link, 1)
Loop

If Len(link) > 7 Then
rtb.SelStart = pos - 1
rtb.SelLength = Len(link)
rtb.SelUnderline = True
rtb.SelColor = vbBlue
End If
pos = InStr(posEnd + 1, LCase$(rtb.Text), "ftp://")
Loop
pos = InStr(1, LCase$(rtb.Text), "ftp://")

Do While pos > 0

For posEnd = pos To Len(rtb.Text)
char = Mid$(rtb.Text, posEnd, 1)
If char = Chr$(32) Or char = Chr$(10) Or char = Chr$(13) Then Exit _
For
Next posEnd
link = Mid$(rtb.Text, pos, posEnd - pos)
char = Right$(link, 1)

Do While char = "." Or char = "," Or char = "!" Or char = "?" Or _
Len(char) <> 1
link = Left$(link, Len(link) - 1)
char = Right$(link, 1)
Loop

If Len(link) > 6 Then
rtb.SelStart = pos - 1
rtb.SelLength = Len(link)
rtb.SelUnderline = True
rtb.SelColor = vbBlue
End If
pos = InStr(posEnd + 1, LCase$(rtb.Text), "ftp://")
Loop
pos = InStr(1, LCase$(rtb.Text), "http://")

Do While pos > 0

For posEnd = pos To Len(rtb.Text)
char = Mid$(rtb.Text, posEnd, 1)
If char = Chr$(32) Or char = Chr$(10) Or char = Chr$(13) Then Exit _
For
Next posEnd
link = Mid$(rtb.Text, pos, posEnd - pos)
char = Right$(link, 1)

Do While char = "." Or char = "," Or char = "!" Or char = "?" Or _
Len(char) <> 1
link = Left$(link, Len(link) - 1)
char = Right$(link, 1)
Loop

If Len(link) > 7 Then
rtb.SelStart = pos - 1
rtb.SelLength = Len(link)
rtb.SelUnderline = True
rtb.SelColor = vbBlue
End If
pos = InStr(posEnd + 1, LCase$(rtb.Text), "http://")
Loop
pos = InStr(1, LCase$(rtb.Text), "www.")

Do While pos > 0

For posEnd = pos To Len(rtb.Text)
char = Mid$(rtb.Text, posEnd, 1)
If char = Chr$(32) Or char = Chr$(10) Or char = Chr$(13) Then Exit _
For
Next posEnd
link = Mid$(rtb.Text, pos, posEnd - pos)
char = Right$(link, 1)

Do While char = "." Or char = "," Or char = "!" Or char = "?" Or _
Len(char) <> 1
link = Left$(link, Len(link) - 1)
char = Right$(link, 1)
Loop

If Len(link) > 4 Then
rtb.SelStart = pos - 1
rtb.SelLength = Len(link)
rtb.SelUnderline = True
rtb.SelColor = vbBlue
End If
pos = InStr(posEnd + 1, LCase$(rtb.Text), "www.")
Loop
rtb.SelStart = Len(rtb.Text)
End Sub
[/code]

SendMessage(RTB_HWND,EM_AUTOURLDETECT,(WPARAM)NULL,(LPARAM)NULL);

there's your one line.

That's the kind of help I'm talking about.  People playing elitism with someone who is trying to learn.

Not one of you posted a correct answer while sitting there chuckling and thinking you're so great.

Only I am great, for I have the correct answer!!

[code]
Option Explicit

Private Const WM_USER = &H400&
Private Const EM_AUTOURLDETECT = (WM_USER + 91)
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 Sub Form_Load()
   Dim lRet As Long
   lRet = SendMessage(rtb.hWnd, EM_AUTOURLDETECT, ByVal 1&, ByVal 0&)
End Sub
[/code]

Grok,
The Evil Visual Basic Guru
(is Evil a modifier of VB or of Guru?)

However just setting EM_AUTOURLDETECT to on was not enough when I tried to do this, it still required subclassing of click events.

Lol...Grok...

Setting the wparam to 0 would disable auto-url detection, not enable it, Etheran. :P

The way to get the app to respond to this is to have the parent window of the RTB handle the EN_LINK message, which is one of the messages received through the standard parent/child WM_NOTIFY message. I'm not sure whether VB makes this easy or not; I haven't had enough experience with VB message handling.

However, if this'll be any help:
EM_AUTOURLDETECT
EN_LINK
WM_NOTIFY

Hmm.. I just realized that any program that uses a RTB can have the links made activatable just by using a SendMessage from another program, right?  hmm :-)

you would need to subclass the richtextbox to detect the links and make them launch, however.

Ah well, it was a thought :P

[quote]you would need to subclass the richtextbox to detect the links and make them launch, however.[/quote]

Actually you don't subclass the RTB...the message you need to deal with is one of the ones the parent window handles via WM_COMMAND.

They won't listen.  The question was for Visual Basic, and I gave them working code which I tested.  If they want to make it more complicated, not much can stop them.

Grok:  Sending EM_AUTOURLDETECT will only underline and highlight links (and set some flags for that text), not handle clicking of those links.  Simply highlighting and underlining the links is not enough which I think Blade_360 would want and others are suggesting.  A sample of how this is done can be found at http://www.developerfusion.com/show/16/12/