您需要在包含helpers.js文件之前声明变量。只需在helpers.js的include上方创建一个脚本标签，然后在其中定义它。
<script type='text/javascript' > var myFunctionTag = false; </script><script type='text/javascript' src='js/helpers.js'></script> ... <script type='text/javascript' > // rest of your pre, which may depend on helpers.js</script>
