The code you have is fairly straightforward.
If you stored your button references in a list, you could simplify it:
// Define this somewhere - it could be once in your constructor
List<Button> buttons = new List<Button> { button1, button2, button3, button4, button5, button6, button7, button8, button9 };
// Given the above, your if becomes:
if (newgame == false && buttons.All(b => b.Text != ""))
{
}
This is really only useful if you're doing multiple checks like this, though...
Reed Copsey, Jr. - http://reedcopsey.com
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