title: Text is not changed with OnClientClick event
body: <p>I'm new to Javascript. I wrote a code, but it does not work as I wish. This is my code.</p>
  
  <pre><code>&lt;script type="text/javascript"&gt;
      function changeText() {
          document.getElementById("demo").innerHTML = 'Hello JavaScript';
      }
  &lt;/script&gt;
  &lt;body&gt;
  &lt;form id="form1" runat="server"&gt;
  &lt;div id="HelloJavaScript" style="height: 157px"&gt;
  
      &lt;p id="demo"&gt;JavaScript can change the HTML content&lt;/p&gt;
  
      &lt;asp:Button ID="Button1" runat="server" Text="Click Me" OnClientClick="changeText()"/&gt;
  
  &lt;/div&gt;
  &lt;/form&gt;
  </code></pre>
  
  <p></p>
  
  <p>The text is not changed once I click the button. What's wrong with this? Thanks in advance.</p>