The suggestion didn't work for me.
Here is an example:
html/aspx
<%@ Page Language="C#" AutoEventWireup="true" Codebehind="Dialog.aspx.cs" Inherits="EOTest.Dialog" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title>Dialog test</title>
</head>
<body>
<form id="form1" runat="server">
<%@ register assembly="EO.Web" namespace="EO.Web" tagprefix="eo" %>
<div class="FieldValue">
<table>
<tr>
<td>
Title:
</td>
</tr>
<tr>
<td>
<a href="javascript:eo_GetObject('UserSelectionDialog').show(true);">(change)</a>
</td>
</tr>
</table>
</div>
<eo:Dialog ID="UserSelectionDialog" runat="server" BackColor="#EBEBEB" Height="100px"
Width="466px" AcceptButton="btnAddUserOwner" AcceptButtonPostBack="True" ControlSkinID="None"
FooterHtml="Dialog Footer" HeaderHtml="Change User Owner" ClientSideOnAccept="accept_handler">
<ContentTemplate>
<div class="FieldLabelDiv">
User Owner:
</div>
<div class="FieldValue FieldValueDD">
<asp:ListBox ID="msOwner" runat="server" SelectionMode="Multiple" Rows="10"></asp:ListBox>
<asp:CustomValidator ID="CVddChangeGroup" runat="server" ErrorMessage="This field requires a selection."
OnServerValidate="msOwner_ServerValidate"></asp:CustomValidator><span id="spanChangeOwnerRequired"
runat="server" visible="false">1</span>
</div>
</ContentTemplate>
<FooterTemplate>
<div class="FieldLabelDiv">
</div>
<div class="FieldValue">
<asp:Button ID="btnAddUserOwner" runat="server" Text="Ok" Width="75px" />
<%--OnClick="btnAddUserOwner_Click"--%>
</div>
</FooterTemplate>
<HeaderStyleActive CssText="padding-right: 3px; padding-left: 8px; font-weight: bold; font-size: 10pt; background-image: url(00020213); padding-bottom: 3px; color: white; padding-top: 0px; font-family: 'trebuchet ms';" />
<BorderImages BottomBorder="00020212" BottomLeftCorner="00020207" BottomRightCorner="00020208"
LeftBorder="00020210" RightBorder="00020211" TopBorder="00020209" TopLeftCorner="00020201"
TopLeftCornerBottom="00020203" TopLeftCornerRight="00020202" TopRightCorner="00020204"
TopRightCornerBottom="00020206" TopRightCornerLeft="00020205" />
<FooterStyleActive CssText="padding-right: 4px; padding-left: 4px; font-size: 8pt; padding-bottom: 4px; padding-top: 4px; font-family: tahoma" />
<ContentStyleActive CssText="padding-right: 4px; padding-left: 4px; font-size: 8pt; padding-bottom: 4px; padding-top: 4px; font-family: tahoma" />
</eo:Dialog>
<span id="spanShowAll" runat="server" visible="false">0</span><span id="spanObjectType"
runat="server" visible="false">0</span>
<script language="javascript" type="text/javascript">
function accept_handler()
{
//Perform all validations and returns false if any of them fail
//Returning false from this handler prevents the dialog from
//closing
if (!Page_ClientValidate())
{
alert('inside');
return false;
}
}
</script>
</form>
</body>
</html>
C#
using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Text;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
namespace EOTest
{
public partial class Dialog : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
if (!Page.IsPostBack)
{
setUserDropDown();
}
}
private void setUserDropDown()
{
msOwner.Items.Insert(0, new ListItem("11111", "1"));
msOwner.Items.Insert(0, new ListItem("22222", "2"));
msOwner.Items.Insert(0, new ListItem("33333", "3"));
msOwner.Items.Insert(0, new ListItem("(All)", ""));
}
protected void msOwner_ServerValidate(object source, ServerValidateEventArgs args)
{
if (msOwner.SelectedIndex == -1)
{
args.IsValid = false;
}
}
}
}