Disable right click option on web page

<script type="text/javascript">

//functions starts for the disable selection

function disableSelection(target){
if (typeof target.onselectstart!="undefined") //IE route
    target.onselectstart=function(){return false}
else if (typeof target.style.MozUserSelect!="undefined") //Firefox route
    target.style.MozUserSelect="none"
else //All other route (ie: Opera)
    target.onmousedown=function(){return false}
target.style.cursor = "default"
}

disableSelection(document.body);
</script>

<script type="text/javascript">
function md(e)
{
 try { if (event.button==2||event.button==3) return false; } 
  catch (e) { if (e.which == 3) return false; }
}
document.oncontextmenu = function() { return false; }
document.ondragstart   = function() { return false; }
document.onmousedown   = md;

//functions ends for the disable selection
</script>