function myEventIE(){ if(event.button == 2){ alert("誠に申し訳ございませんが右クリックはできません");}}
function myEventNN(myEvent){ if(myEvent.which == 3){ alert("誠に申し訳ございませんが右クリックはできません");return false;}}
if(document.all){ document.onmousedown = myEventIE ;}if(document.layers)
{ document.captureEvents(Event.MOUSEDOWN);document.onmousedown = myEventNN ;}