思路：把页面中所有的标签放到一个div中，然后再再最后添加一个空div标签fadeDiv，用fadeDiv遮挡body使fadeDiv渐现
<title></title>
<script src="../jquery132min.js" type="text/javascript"></script>
<script type="text/javascript">
$(function() {
var p = $("body");
var offset = p.offset();
$("#fadeDiv").css({ top: offset.top, left: offset.left, width: $("#bodyDiv").width(), height: $("body").height(), backgroundColor: "white", opacity: 1, position: "absolute" });
if (jQuery.isReady) {
$("#fadeDiv").fadeOut(1000);
}
})
</script>
$(function() {
var p = $("body");
var offset = p.offset();
$("#fadeDiv").css({ top: offset.top, left: offset.left, width: $("#bodyDiv").width(), height: $("body").height(), backgroundColor: "white", opacity: 1, position: "absolute" });
if (jQuery.isReady) {
$("#fadeDiv").fadeOut(1000);
}
})
</script>
</head>
<body>
<form >
</div>
</form>
</body>
</html>
<body>
<form >
</div>
</form>
</body>
</html>