title: Allow Only AlphaNumeric in textbox using JQUERY
body: <p>I found following code here at :</p>
  
  <p><a href="https://stackoverflow.com/questions/24774367/how-to-validate-html-textbox-not-to-allow-special-characters-and-space">How to validate html textbox not to allow special characters and space?</a></p>
  
  <p>So Ive written this code for validation, but it is not working.</p>
  
  <pre><code>&lt;script type="text/javascript" src="js/jquery.js"&gt;&lt;/script&gt;
  &lt;script type="text/javascript" src="js/jquery.validate.min.js"&gt;&lt;/script&gt;
  
  &lt;input type="text" name="txtUsername" id="txtUsername" data-validation="alphanumeric" data-validation-allowing="_" value=""&gt;
  </code></pre>
  
  <p>Should I write any script to not allow special characters in textbox.</p>