This event fires before the writeHtml() or getHtml() method is executed.

Syntax

ASP.NET

<script type="text/javascript">
function Uploader1_PreRender(){
    //...your code...
}
</script>
<aur:Uploader ID="Uploader1" runat="server">
    <ClientEvents>
        <aur:ClientEvent EventName="PreRender" HandlerName="Uploader1_PreRender" />
    </ClientEvents>
</aur:Uploader>

PHP

<script type="text/javascript">
function Uploader1_PreRender(){
    //...your code...
}
</script>
<?php
    $Uploader = new Uploader("Uploader1");
    //...other params...
    $Uploader->getClientEvents()->setPreRender("Uploader1_PreRender");
    //...other params...
    $Uploader->render();
?>

JavaScript

function Uploader1_PreRender(){
    //...your code...
}
$au.uploader({
    events: {
        //...other params...
        preRender: [Uploader1_PreRender],
        //...other params...
    }
})