title: copy text from one textbox to another based on a condition
body: <p>I am working on javascript. </p>
  
  <p>Consider two textboxes tb1 and tb2 respectively</p>
  
  <p>The value present in tb1 should be copied in tb2 based on a condition. If the condition is true nothing needs to be copied. If the condition is false the value in tb1 should also be initialised to tb2. Is it possible..</p>