Clickable URL in a Winform Message Box?

Solution 1:

One option is display the url in the message box, along with a message and provide the help button that takes you to that url:

MessageBox.Show(
    "test message",
    "caption",
    MessageBoxButtons.YesNo,
    MessageBoxIcon.Information,
    MessageBoxDefaultButton.Button1,
    0, '0 is default otherwise use MessageBoxOptions Enum
    "http://google.com",
    "keyword")

Important to note this code cannot be in the load event of the form, the Help button will not open the link.

Solution 2:

You can use the LinkLabel control on your own Form for this. Unfortunately, the MessageBox form cannot be customized in this way, so you would need to create your own Form to mimic the MessageBox for your purposes.

Solution 3:

MessageBox won't do that. You'll either need to use the TaskDialog (introduced in Vista) or create your own dialog.

--Edit--
There are ways to fake the task dialog on XP. There are a few articles on CodeProject.com that I've used in the past.

Solution 4:

You have to create your own form, instead of the built-in MessageBox, and you can use a LinkLabel on it.

However on the built-in MessageBox a Help button could be displayed among the buttons.