// source http://jsbin.com/sidiwipupe

index.html

<script src="http://code.jquery.com/jquery-latest.js"></script>
  
<div>
    <p>Some cool text!</p>
    <br/>
    <p>Some cool text!</p>
</div>

<div id="all-select">
    <p>Some cool text!</p>
    <br/>
    <p>Some cool text!</p>
</div>
<script id="jsbin-javascript">
$.fn.OneClickSelect = function(){
      return $(this).on('click',function(){
        
         var range, selection;
         if (window.getSelection) {
            selection = window.getSelection();        
            range = document.createRange();
            range.selectNodeContents(this);
            selection.removeAllRanges();
            selection.addRange(range);
        } else if (document.body.createTextRange) {
            range = document.body.createTextRange();
            range.moveToElementText(this);
            range.select();
        }
      });
    };
    
    // Apply to these elements
    $('p, #all-select').OneClickSelect();
</script>


<script id="jsbin-source-javascript" type="text/javascript">    $.fn.OneClickSelect = function(){
      return $(this).on('click',function(){
        
         var range, selection;
         if (window.getSelection) {
            selection = window.getSelection();        
            range = document.createRange();
            range.selectNodeContents(this);
            selection.removeAllRanges();
            selection.addRange(range);
        } else if (document.body.createTextRange) {
            range = document.body.createTextRange();
            range.moveToElementText(this);
            range.select();
        }
      });
    };
    
    // Apply to these elements
    $('p, #all-select').OneClickSelect();</script>

jsbin.sidiwipupe.js

$.fn.OneClickSelect = function(){
      return $(this).on('click',function(){
        
         var range, selection;
         if (window.getSelection) {
            selection = window.getSelection();        
            range = document.createRange();
            range.selectNodeContents(this);
            selection.removeAllRanges();
            selection.addRange(range);
        } else if (document.body.createTextRange) {
            range = document.body.createTextRange();
            range.moveToElementText(this);
            range.select();
        }
      });
    };
    
    // Apply to these elements
    $('p, #all-select').OneClickSelect();