title: How to increase value stored in session storage
body: <p>I need to set value of a variable in session storage as 0.</p>
  
  <p>Then check the value of the session storage whether it is less than a constant. If so assign a value to a variable and increment the value in session storage by 1.</p>
  
  <p>How can I do this, please help me with a simple example.</p>