auto height in multiline textbox

I have to show data from database with multiline textbox.

How can i set height开发者_StackOverflow中文版 auto in this multiline textbox?

My code is here,

<asp:TextBox ID="txtNaiyo" runat="server" TextMode="MultiLine" Rows="5" Width="100%" style="height:auto;" Value='<%# Eval("Naiyo") %>'/>

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I've made something quite easy. First I put the TextArea into a DIV. Second, I've called on Ready Function to this script

<div id="divTable">
  <textarea ID="txt" Rows="1" TextMode="MultiLine" />
</div>

$(document).ready(function () {
  var heightTextArea = $('#txt').height();
  var divTable = document.getElementById('divTable');
  $('#txt').attr('rows', parseInt(parseInt(divTable .style.height) / parseInt(altoFila)));
});

Simple. Is the Max Height of the div once is render, divided the height of one TextArea of one row.