Sample Code - How to use Tab key in Textarea

[Javascript] How to use Tab key in Textarea

<script> 
function useTab(el){ 
    if(9==event.keyCode){ 
        (el.selection=document.selection.createRange()).text="\t"; 
        event.returnValue=false; 
    } 
} 
</script> 

<textarea cols=40 rows=10 onkeydown="useTab(this)"></textarea>