How to get the values from Fckeditor control from javascript

i am using FckEditor control in asp.net
this is required field
so at the time of save button i want to validate this control in javascript.

i dont know how to get the contents from this control...
please send me ur reply....





<%@ Register TagPrefix="FCKeditorV2" Namespace="FredCK.FCKeditorV2" Assembly="FredCK.FCKeditorV2" %>
<table>
<tr>
<td >Short Story Description<span class="required" >*</span><br>(Maximum 300 characters)</td>
<td ><FCKeditorV2:FCKeditor id="TxtRShortDescription" height="400px" BasePath= "FCKeditor/" runat="server" /></td>
<td><asp:Button id="btnSave" runat="server" Text="Save" OnClick="Save" TabIndex="4"></asp:Button></td>
</td>
</tr>
</table>

btnUpdate.Attributes.Add("onClick","return DoValidateForm('Update')");



Thanks in advance
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