Print Page If Form Is Valid?

If button is clicked, want form to be validated. If the validation passes then bring up print dialogue

I have got the validation (using dreamweaver) working, however if the form is correct , how do I get the print dialogue (window.print()) to appear?

here's the code

<script language="JavaScript" type="text/JavaScript">
<!--
function MM_findObj(n, d) { //v4.01
var p,i,x; if(!d) d=document; if((p=n.indexOf("?"))>0&&parent.frames.length) {
d=parent.frames[n.substring(p+1)].document; n=n.substring(0,p);}

[Code].....