title: How to do validation on textfield?
body: <p>I am making a registration form, in which I have 8 text fields and one submit button.</p>
  
  <p>Whenever the user fails to enter one of the text fields, upon click of submit button an error message should be generated.</p>
  
  <p>And when the user fills all the text fields, on click of submit button it should go to the next page.</p>
  
  <p>Please give me some advice, thanks.</p>