copy multiple textareas with same button

 var copyText = document.getElementsByClassName("form-control")[0];
 function myFunction() {

     // Get the text field

     // Select the text field
     copyText.select();
     copyText.setSelectionRange(0, 99999); // For mobile devices

     // Copy the text inside the text field
     document.execCommand("copy");

     // Alert the copied text
     alert("Copied the text: " + copyText.value);

     ///second

 } 

<textarea class="form-control" tabindex="0">something</textarea>
 <button  onclick="myFunction()">clickme</button>
<textarea class="form-control"tabindex="3" >something1</textarea>
 <button  onclick="myFunction()">clickme</button>
<textarea class="form-control" >something2</textarea>
 <button onclick="myFunction()">clickme</button>