[Javascript] Impedire la selezione del testo

<script type="text/javascript">

//form tags to omit in NS6+:
var omitformtags=["input", "textarea", "select"]

omitformtags=omitformtags.join("|")

function disableselect(e){
if (omitformtags.indexOf(e.target.tagName.toLowerCase())==-1)
return false
}

function reEnable(){
return true
}

if (typeof document.onselectstart!="undefined")
document.onselectstart=new Function ("return false")
else{
document.onmousedown=disableselect
document.onmouseup=reEnable
}

</script>