<?php
$base = "https://chart.googleapis.com/chart?";
echo $base;
echo "<form action='$base' method='POST'>
  <input type='hidden' name='cht' value='qr' />
  <input type='hidden' name='chs' value='300x300' />
  <input type='text' name='chl' placeholder ='What's on your mind?' value='' />
  <input type='submit'  />
</form>
"
?>