title: PHP - Check if user's entered date is of future or of today
body: <p>I have a textbox to enter Date.</p>
  
  <p>What should the code look like to check if the user's entered date is of future or of today?</p>
  
  <p>I also want the users' to enter date in dd/mm/yyyy format.</p>
  
  <p>The code will give an error if any of them fails.</p>