title: Javascript how to search double byte string with single byte string and vice versa
body: <p>I have a string </p>
  
  <pre><code>var str = "か22222";
  </code></pre>
  
  <p>i want to search like this</p>
  
  <p>str.indexOf("か２"); where "か２" both are multi byte characters and "str" has only "か" as multibyte</p>
  
  <p>but still I should get the result of indexOf as 0.</p>
  
  <p>is there any way of doing this is JS ??</p>