为什么我在浏览器中出错？
TypeError:document.body为null
代码在JSfiddle中运行良好.
HTML
<head>
<meta charset="UTF-8">
<title></title>
<script src="jsscript.js"></script>
</head>
<body>
</body>
JS
var creElem = document.createElement("p");
creElem.innerHTML = "Hellow World";
creElem.setAttribute("id", "id_name");
document.body.appendChild(creElem);