监听esc键 关闭dialog dwz框架

document.onkeydown = function(e){ // alert(1) var keycode = "";  if(navigator.appName == "Microsoft Internet Explorer")       {           keycode = event.keyCode;           // var realkey = String.fromCharCode(event.keyCode);       }else{           keycode = e.which;           // var realkey = String.fromCharCode(e.which);       }       if(keycode == "27"){       // alert(27)       $.pdialog.closeCurrent()       }       // alert("按键码: " + keycode + "字符: " + realkey); }