tu mets ca dans le header de la page :
<script language="JavaScript1.2">
function popUp (url, width, height) {
var top=(screen.height-height)/2;
var left=(screen.width-width)/2;
window.open(url,
"",
"top=" + top
+ ",left=" + left
+ ",width=" + width
+ ",height=" + height
+ ",status=0,titlebar=0,scrollbars=1,resizable=1",
"_blank"
);
}
</script>
puis la ou tu veux ouvrir la popup (par ex ds le <body> ):
<body onLoad="javascript:popUp('ma_page.html',screen.width/4, screen.height/4);" >
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