title: why my html (jquery) gives undefined variable?
body: <p>I have an undefined variable issue even though I believe myself they are declared. I am trying to declare class as a variable and in this, some files are associated each other.</p>
  
  <p>Error message says: <code>wd is not defined</code>. </p>
  
  <blockquote>
    <p>wd.onWebPageChange() -- in A.js</p>
  </blockquote>
  
  <p>Below are the references:</p>
  
  <pre><code>&lt;head&gt;
      &lt;!-- jQuery &amp; jQuery UI + theme (required) --&gt;
      &lt;link href="jquery-ui.css" rel="stylesheet"&gt;
      &lt;script src="jquery.js"&gt;&lt;/script&gt;
  
      &lt;script src="A.js"&gt;&lt;/script&gt;
      &lt;script src="B.js"&gt;&lt;/script&gt;
  &lt;/head&gt;
  &lt;body&gt;
            &lt;input name="webPage" type="text" onchange="wd.onWebPageChange()" onkeyup="wd.onWebPageChange()"/&gt;
            &lt;input id="getButton" type="button" value="GET" onclick="wd.onGet()"/&gt;
  &lt;/body&gt;
  </code></pre>
  
  <p><br>
  <strong>Update 1:</strong>, </p>
  
  <p>From <code>A.js</code>, I found below, the functions are belong to <code>WebDriverJsController</code> :</p>
  
  <pre><code>document.addEventListener("DOMContentLoaded", function(event) {
    window.wd = new WebDriverJsController();
  });
  </code></pre>
  
  <p><strong>Tried it with</strong> </p>
  
  <blockquote>
    <p>wd.onWebPageChange() -> <code>window.wd.onWebPageChange()</code> in the same position, </p>
  </blockquote>
  
  <p>it says that <code>not defined or cannot get null referenced attributes</code></p>
  
  <p><strong>Update 2:</strong> grep: wd</p>
  
  <pre><code>---------- BASE64-ARRAYBUFFER.JS
  ---------- FILESAVER.JS
  ---------- HAMMER.JS
  ---------- HAMMER.MIN.JS
  ---------- JQUERY-UI.CSS
  ---------- JQUERY-UI.JS
  ---------- JQUERY.JS
  ---------- JQUERY.KEYBOARD.JS
  ---------- KEYBOARD.CSS
  ---------- QML_VIEW_VISUALIZER.XSL
  
  ---------- WEBDRIVER-APP.JS
    window.wd = new WebDriverJsController();
  
  ---------- WEBDRIVER.JS
  webdriver.AbstractBuilder.SERVER_URL_ENV = "wdurl";
  webdriver.AbstractBuilder.DEFAULT_SERVER_URL = "http://localhost:4444/wd/hub";
  webdriver.Builder.SESSION_ID_ENV = "wdsid";
  
  ---------- WEBDRIVERJSDEMO.HTML
  &lt;input name="webPage" type="text" onchange="wd.onWebPageChange()" onkeyup="wd.onWebPageChange()"/&gt;
  &lt;input id="getButton" type="button" value="GET" onclick="wd.onGet()"/&gt;
  </code></pre>