也许是这样的:
<script>if(!window.jQuery){ var script = document.createElement('script'); script.type = "text/javascript"; script.src = "path/to/jQuery"; document.getElementsByTagName('head')[0].appendChild(script);}</script>
也许是这样的:
<script>if(!window.jQuery){ var script = document.createElement('script'); script.type = "text/javascript"; script.src = "path/to/jQuery"; document.getElementsByTagName('head')[0].appendChild(script);}</script>