js 屏蔽右键

function clickIE4()

{

if (event.button==2){

return false;

}

}

function clickNS4(e)

{

if (document.layers||document.getElementById&&!document.all)

{

if (e.which==2||e.which==3){

return false;

}

}

}

if (document.layers){

document.captureEvents(Event.MOUSEDOWN);

document.onmousedown=clickNS4;

}

else if (document.all&&!document.getElementById){

document.onmousedown=clickIE4;

}

document.oncontextmenu=new Function("return false");

// disable the BackSpace(8), ALT+Left(37), ALT+Right(39), ALT+HOME(36), Enter (13), N(78), n(110)

var ALREADY_CHECKED = false;

function KeyIE4()

{

if(event != null){

var oSource = event.srcElement;

if (ALREADY_CHECKED) {

if ((oSource != null && (oSource.type=="text" || oSource.type=="textarea")) && ("8" == event.keyCode || "35" == event.keyCode || "36" == event.keyCode || "37" == event.keyCode || "39" == event.keyCode || "46" == event.keyCode || (event.ctrlKey && "88" ==
event.keyCode))) {

return true;

} else {

return false;

}

} else {

if("8" == event.keyCode && (oSource ==null || (oSource != null && oSource.type!="text" && oSource.type!="textarea"))){

return false;

} else if(event.altKey && ("36" == event.keyCode || "37" == event.keyCode || "39" == event.keyCode)){

return false;

}else if(event.ctrlKey && ("78" == event.keyCode || "110" == event.keyCode)){

return false; // Ctrl + N, restrict for now

}else if("13" == event.keyCode && (oSource ==null || (oSource != null && oSource.type!="textarea"))){

return false;

}else{

return true;

}

}

}

}

document.onkeydown = KeyIE4;

document.onkeyup = KeyIE4;