FIRST of all…this is not a forum dedicated to the Delphi programming language–it is instead concerned with the FIRST robotics competition, of which ChiefDelphi is a participating team. (So posting Delphi programming questions here is generally a bad idea.) That much said, I do know something about Delphi, so you may find this useful, just this once. (There are a number of good Delphi references on the internet–search for them. Try delphibasics.co.uk, and delphi.about.com, for example.)
Now, for the programming: Is there any reason why you can’t use the OnClick event to call ShellExecute with the appropriate webpage as a parameter? (You may need to include the ShellAPI unit in the uses statement.) Maybe something like this:
ShellExecute(Handle, 'open', 'http://www.chiefdelphi.com', Nil, Nil, SW_SHOWNORMAL);
Or, if you need to select a specific webpage for each node, use the OnChange event’s Node parameter to identify the correct node, every time focus changes, and cross-reference it with an array of links to pages, then call ShellExecute to launch the browser.
Note that this will spawn a new default browser window. If you want to have the links open inside of your program, you’ll probably have to use an ActiveX browser control (that’s too hard to explain here, if you’re not familiar with it), and instruct the browser control to open the page, instead of using ShellExecute.
Also note that using a TTreeView to display links to webpages is a very non-standard style, so be careful not to violate the user interface guidelines for Windows programs. Usually, a hyperlink would be blue, underlined, and obvious, instead of disguised in a TTreeView.
To reiterate–don’t post Delphi programming questions here any more, it’s usually not worth it! 