Under Button1_Click add the following code:
Note: Movie1 is the ShockWave Flash Player. Rename 'Movie1' to whatever yours is named.
Code:
If TextBox1.Text = "0"
MessageBox.Show("Invalid XAT CBOX ID.")
Else
Movie1.Movie = "http://www.xatech.com/web_gear/chat/chat.swf?id=" + TextBox1.Text
End If
This basically sets the movie to 'http://www.xatech.com/web_gear/chat/chat.swf?id=' and whatever the text of 'TextBox1.Text' is. You can add more methods to make sure its numerical only, but this is the basic source and will do what i think you are wanting to be done.