Set diferent opacity to a color.

I've done a little Notepad clone with VB2003

It works great. Now, what I want to do is to set different opacity to my text area (is a richtextbox object), which should be seted on runtime by a trackbar.

I want it to be just like this picture, setting the background area but not any of the text typed.

http://ez.no/var/ezno/storage/images..._ini_files.png

Can I do this?

I thought that I could set the richtextbox background color to a "almost" white (RGB:254,254,254), to be more simple to detect the area that I want to set a different opacity.

Thank you.

Have a look at this : http://www.vbforums.com/showthread.p...ht=transparent

Very appreciated but this is not what I'm trying to do.

VB2003 permit doing this without using API but using the form property "TransparencyKey".

I'm talking about setting opacity and not transparency. I would like to set opacity, for instance, to 60%. Transparency only permits opacity equal to 0% or 100%.

Thank you.

Sorry, I missed the part about .Net. I moved to that forum, since as i understand it's a .Net specific question.

I've also posted this at the .Net forum and I thought that it would be better to post this at the API forum, because .net2003 does not have any capability to do what I want.
Sorry for any misunderstood.

Thank you.

OK, moved it back. Sorry for the mixup...