This is done via JavaScript.
Try this:
Code:
<script language="JavaScript" type="text/javascript">
<!--
//Opens a new window with the specified properties.
function openWin(pageHref, pageName, pageWidth, pageHeight)
{
var center_t = (screen.height - pageHeight) / 2;
var center_l = (screen.width - pageWidth) / 2;
props = 'height=' + pageHeight + ' ,width=' + pageWidth+' ,top=' + center_t+' ,left=' + center_l+' ,scrollbars=yes ,noresize';
show = window.open(pageHref, pageName, props);
show.window.focus();
return true; // Return false if you want the link to be defunct.
}
//-->
</script>
Call it like this:
Code:
onclick="return openWin('url', 'page_name', 740, 543);"
Regards.
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