CSS
Let's make nice see thru background:
.modalBackground
{
background-color:#CCCCFF;
filter:alpha(opacity=40);
opacity:0.5;
}
Position should be -1000px, so during loading you not gonna see popup initialization.
.ModalWindow
{
border: solid1px#c0c0c0;
background:#f0f0f0;
padding: 0px10px10px10px;
position:absolute;
top:-1000px;
}
ASPX
<ajaxToolkit:ModalPopupExtenderID="ModalPopupExtender1"runat="server"
TargetControlID="lnkPopup"
PopupControlID="panEdit"
BackgroundCssClass="modalBackground"
CancelControlID="btnCancel"
PopupDragHandleControlID="panEdit">
</ajaxToolkit:ModalPopupExtender>
<asp:PanelID="panEdit"runat="server"Height="180px"Width="400px"CssClass="ModalWindow">
<h1>Edit/h1>
<table width="100%">
<tr>
<td class="formtext" style="height: 23px; width: 150px;" align="left">
Fields1:
</td>
<td>
<asp:TextBox ID="txtFields1" runat="server"></asp:TextBox>
</td>
</tr>
</table>
<br />
<asp:Button ID="Button1" runat="server" Text="Update" OnClick="btnUpdate_Click"/>
<asp:Button ID="btnCancel" runat="server" Text="Cancel" />
</asp:Panel>
<a id="lnkPopup" runat="server">Show Popup</a>