AJAX :: Hide A Modal Popup When Another Modal Popup Is Shown

I have three modal popup and three link buttons the first link button is on menu i.e. login that shows login-popup and the login popup contains two links forgot password and register both of them opens a popup but the problem is the login popup isnt hiding with click on register or foreget link the popups are appearing perfectly but arent hiding.

The html for all three popup is as shown below:-

 <cc1:ModalPopupExtender ID="Modallogin" runat="server" PopupControlID="loginpanel" TargetControlID="loginlink" BackgroundCssClass="modalBackground"
CancelControlID="lnkforgot">
</cc1:ModalPopupExtender>
<asp:Panel ID="loginpanel" runat="server" CssClass="modalPopup">

[Code] .....

And the codebehind file that i wrote some code which also isnt working is as shown below:-

protected void Button2_Click(object sender, EventArgs e) {
Modalforget.Hide();
} protected void lnkregister_Click(object sender, EventArgs e) {
Modallogin.Hide();
Modalregister.Show();

[Code] ....

I also used breakpoints on link click event and are not going to code behind file on click and popup is just shown without hiding the other. And the css used is I found on aspsnippet site!