title: How to call javascript function when value in textarea was change?
body: <p>How to call javascript function when value in textarea was change ?</p>
  
  <p>When fill data into textarea <code>id="yyyy"</code>, textarea <code>id="xxxx"</code> will change value too. This function are work good.</p>
  
  <p>When textarea <code>id="xxxx"</code> change value, i want to call function <code>check2</code> , how can i do ?</p>
  
  <p>please do not change code in function <code>check</code> and <code>id="yyyy"</code></p>
  
  <p><a href="https://jsfiddle.net/9b6h897d/3/" rel="nofollow noreferrer">https://jsfiddle.net/9b6h897d/3/</a></p>
  
  <pre><code>&lt;textarea id="yyyy" onkeyup="check(this.value)"&gt;&lt;/textarea&gt;
  &lt;textarea id="xxxx" onchange="check2(this.value)" &gt;&lt;/textarea&gt;
  
  &lt;script&gt;
  function check(value){
      document.getElementById("xxxx").value = value;
  }
  function check2(value){
      alert(value);
  }
  &lt;/script&gt;
  </code></pre>