title: How to implement input checkbox's checked action?
body: <p>In a WebForm I have an <code>input checkbox</code> to which I wanna apply server side action. 
  For example, when the checkbox is checked, I want to change some label's text.
  I have tried to use on client side:</p>
  
  <pre><code>&lt;input id="auto" name="auto" type="checkbox" data-toggle="toggle" data-on="AUTOMAT" data-off="MANUAL" &lt;%= string.IsNullOrEmpty(Request["auto"]) ? string.Empty : "checked" %&gt; /&gt;
  &lt;asp:Label ID="Label3" runat="server" Text="Label"&gt;&lt;/asp:Label&gt;   
  &lt;asp:HiddenField ID="customSwitch1Change" runat="server" Value="0" /&gt;
          &lt;script&gt;
              $('#auto').click(function () {
                  $('#&lt;%=customSwitch1Change.ClientID%&gt;').val("1");
                  $('#form1').submit();
              });
          &lt;/script&gt;
  </code></pre>
  
  <p>I have used <a href="https://gitcdn.github.io/bootstrap-toggle/2.2.2/css/bootstrap-toggle.min.css" rel="nofollow noreferrer">this</a> and <a href="https://gitcdn.github.io/bootstrap-toggle/2.2.2/js/bootstrap-toggle.min.js" rel="nofollow noreferrer">this</a> for the input checkbox.</p>
  
  <p>On the server-side I have tried:</p>
  
  <pre><code>protected void CustomSwitch1Change(string auto)
  {
  
      if (string.IsNullOrEmpty(auto))
      {
          Label3.Text = $"customSwitch1 was not checked.";
      }
      else
      {
          Label3.Text = $"customSwitch1 was checked and the check value is {auto}.";
      }
  }
  </code></pre>
  
  <p>But what I've tried is not working.
  What I'm doing wrong? Or is there another way to do this?</p>