title: how to enable the comment buttons in visual studio
body: <p><img src="https://i.stack.imgur.com/5kAA3.png" alt="enter image description here">I am using visual studio.
  In the tool bar,"comment" and "uncomment" buttons are disabled.
  and If I use <kbd>Ctrl + K</kbd> and <kbd>Ctrl + C</kbd>` also ,I am not able to comment the code.
  how to solve this?</p>