title: Special character validation using JavaScript
body: <p>Special characters  <code>&lt;</code>, <code>&gt;</code>, <code>%</code>, <code>''</code>, <code>""</code>, <code>$</code> and <code>^</code> are not allowed in a textbox. I need to put a validation check to restrict these characters on submit along with the null check.</p>
  
  <p>I wrote entire validation code in a function and calling it on click of the submit button, but the function is not recognised on click.</p>
  
  <p>Please help me write some JavaScript code to achieve this functionality.</p>