adjust text box size if text is too big to fit in its original size

 
Hi,
On mouseover of hypertext, I call function in javascript & print text in textbox. As shown following:
<a  href=""  onclick="home() >
 </a>
 
function home()
{
var TB=document.getElementById ("<%=txtbox.ClientID%>");
TB.value="HELLO THERE "
}

 
But if the text to be printed is too big to fit in text box, then text box size  (height, width)should get adjusted .
Is there any property of textbox to achieve this?

 
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