ASP Source Code

copy data between form fields by javascript  JavaScript: <script type="text/javascript"> function CopyAddress() { if(document.getElementById("ctl00_cphhead_chkpresentaddress").checked) { document.getElementById("ctl00_cphhead_txtpermantaddress").value=document.getElementById("ctl00_cphhead_txtaddress").value; } else { document.getElementById("ctl00_cphhead_txtpermantaddress").value=""; } } </script> Present Address TextBox:     <asp:TextBox ID="txtaddress" runat="server" TextMode="MultiLine" Height="50px"                     Width="140px" onkeyup="CopyAddress();"></asp:TextBox></td> CheckBox: <asp:CheckBox ID="chkpresentaddress" runat="server" onclick="CopyAddress();" />