实例如下：
[removed]
[removed] = check;
function check(e) {
var code;
if (!e) var e = window.event;
if (e.keyCode) code = e.keyCode;
else if (e.which) code = e.which;
if (((event.keyCode == 8) && //BackSpace
((event.srcElement.type != "text" &&
event.srcElement.type != "tex
