how to redirect to another page in javascript on submit type

<script type="text/javascript" language="javascript">
function redirect()
{
    window.location.href="login.php";
}
</script>
<form  name="form1" id="form1" method="post">  
    <input type="submit" class="button4" name="order" 
        id="order" value="Place Order" onclick="redirect();" >
</form>