ejs文件中的“未定义文档”错误,该文件将与node.js中的res.render()一起使用?

Ada*_*h D 2 javascript node.js express

我有这个ejs文件,该文件将在node.js中使用res.render()作为响应发送

<!DOCTYPE html>
<html>
<head>  
  <title>pilcit</title>
</head>
<body>
<% var btn = document.getElementById('btn');%>
<% btn.style.background="blue"; %>
<div class="pt-5">
<div class="container-fluid">
    <h1  style="color:blue;" align=center>Pilcit</h2>
    <h4 style="color:#369bf4" align="center">The online clipboard</h4>

     <div>

         <textarea  class="form-control mt-5" name="content" rows="12">
            <%= result.content %>
         </textarea>
         <input type="text" value="sdfdsfsdfsd"  id="foo">
         <button id="btn" data-clipboard-target="#foo" copy clip </button>


    </div>  
    <!--<input type="submit" value="Create Clip">-->

</div>
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但行
`<%var btn = document.getElementById('btn');%>

给我这个错误

ReferenceError: /home/ubuntu/workspace/pilcit/views/show.ejs:34
32| </head>
33| <body>
 >> 34|     <% var btn = document.getElementById('btn');%>
35| <div class="pt-5">
36| 
37|     <div class="container-fluid">

document is not defined
at eval (eval at compile (/home/ubuntu/workspace/pilcit/node_modules/ejs/lib/ejs.js:618:12), <anonymous>:17:27)
at returnedFn (/home/ubuntu/workspace/pilcit/node_modules/ejs/lib/ejs.js:653:17)
at tryHandleCache (/home/ubuntu/workspace/pilcit/node_modules/ejs/lib/ejs.js:251:36)
at View.exports.renderFile [as engine] (/home/ubuntu/workspace/pilcit/node_modules/ejs/lib/ejs.js:482:10)
at View.render (/home/ubuntu/workspace/pilcit/node_modules/express/lib/view.js:135:8)
at tryRender (/home/ubuntu/workspace/pilcit/node_modules/express
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我没有使用<%var btn = document.getElementById('btn');%>来更改btn的背景颜色,我想将其与剪贴板js一起使用。我用那条线检查嵌入式JavaScript是否正常工作。

sch*_*u34 6

您无法document在ejs标记内使用,因为该代码在服务器上执行。相反,您应该添加一个脚本标记,该标记将在页面实际加载到浏览器中后立即运行。

<script> var btn = document.getElementById('btn'); </script>
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