منع استخدام زر الماوس اليمين للصور

<script language="JavaScript1.2">

/*
Disable right click script II (on images)- By Dynamicdrive.com
For full source, Terms of service, and 100s DTHML scripts
Visit http://www.dynamicdrive.com
* Translated By www.star28.com/
*/

var clickmessage="الزر اليمين لا يعمل على الصور "

function disableclick(e) {
if (document.all) {
if (event.button==2||event.button==3) {
if (event.srcElement.tagName=="IMG"){
alert(clickmessage);
return false;
}
}
}
else if (document.layers) {
if (e.which == 3) {
alert(clickmessage);
return false;
}
}
else if (document.getElementById){
if (e.which==3&&e.target.tagName=="IMG"){
alert(clickmessage)
return false
}
}
}

function associateimages(){
for(i=0;i<document.images.length;i++)
document.images[i].onmousedown=disableclick;
}

if (document.all)
document.onmousedown=disableclick
else if (document.getElementById)
document.onmouseup=disableclick
else if (document.layers)
associateimages()
</script>