title: indexOf is not working in JavaScript
body: <p>I am checking an index Of string in JAVASCRIPT. and this is coming as false. where as the value does belong to it as below :</p>
  
  <pre><code>if(idOfControl.indexOf(idOfButton))  == is giving false for the below values.
  
  idOfControl  = "dlInventory_btnEditComment_0"
  idOfButton   = "dlInventory_btnEditComment"
  </code></pre>
  
  <p>But if I run  <code>idOfControl.replace(idOfButton, "");</code> It is working and replacing the text.</p>
  
  <p>Any reason for this?</p>