title: How can I make the HTML5 input required attribute behave with .NET?
body: <p>I am using ASP.NET 4.</p>
  
  <p>My UI depends on using an update panel. Updating certain UI elements requires a PostBack which is handled by the ScripManager. Basic stuff. These action occur before the fields are submitted.</p>
  
  <p>The problem comes in with the HTML5 markup that have to deal with.</p>
  
  <pre><code>&lt;input type="text" id="foo" aria-required="true" required&gt;
  </code></pre>
  
  <p>Using a .NET TextBox control and adding attributes, I get rendered code as such:</p>
  
  <pre><code>&lt;input name="foo" type="text" id="foo" aria-required="true" required="required" /&gt;
  </code></pre>
  
  <p>The HTML5 behavior is that each time a PostBack occurs, the input field thinks it should alert the user, since no value is present in the field, even though the user if off doing other actions within the UI.</p>
  
  <p>Is there a way to bring this HTML5 behavior under control, such that the the INPUT field ignores PostBack?</p>