ASP.NET

DisplayMode = dMode;
FolderAlias = _folderAlias;
SqlConnection conn = new SqlConnection(@"Data Source= .;Initial Catalog=MXContact.NET_Demo_100401;Integrated Security=true;");

SqlCommand cmd = new SqlCommand();
cmd.Connection = conn;
cmd.CommandType = CommandType.StoredProcedure;
cmd.CommandText = "stbFormPropertiesToXML";    //stored procedure
SqlDataAdapter frmDA = new SqlDataAdapter(cmd.CommandText, cmd.Connection);
DataSet FormPropertiesDS = new DataSet();

try
{
    conn.Open();
    cmd.Parameters.Add(new SqlParameter("@displayMode", SqlDbType.NVarChar));
    cmd.Parameters["@displayMode"].Direction = ParameterDirection.Input;

    cmd.Parameters.Add(new SqlParameter("@folderAlias", SqlDbType.NVarChar));
    cmd.Parameters["@folderAlias"].Direction = ParameterDirection.Input;


    cmd.Parameters["@displayMode"].Value = DisplayMode;
    cmd.Parameters["@folderAlias"].Value = FolderAlias;

    cmd.ExecuteNonQuery();
    frmDA.Fill(FormPropertiesDS);
    conn.Close();

    FormPropertiesDS.WriteXml("FormProperties.xml");
    //FormPropertiesDS.WriteXml(MapPath("FormProperties.xml"));
}
catch (Exception ex)
{
    errorMsg = ex.Message;
}
finally
{
    conn.Close();
}

ALTER PROCEDURE [dbo].[stbFormPropertiesToXML]
@displayMode NVARCHAR(2),
@folderAlias NVARCHAR(30)

AS

SELECT	*
FROM	[stbFormProperties]
WHERE	[FolderKey]		=	(SELECT [FolderKey] FROM [stbFolders] WHERE [FolderAlias] =	@folderAlias)
AND		[DisplayMode]	=	@displayMode

var x = window.parent.document.getElementById('ctl00$contentBody$hdnApplicationIndex').value

<asp:HiddenField ID="hdnApplicationIndex" Value="0" runat="server" />
<asp:Button ID="btnHidden" runat="server" style="display: none" />
<ajaxToolkit:ModalPopupExtender ID="mpeUser" runat="server"
    CancelControlID="btnCancel"
    OkControlID="btnOK"
    TargetControlID="btnHidden"
    PopupControlID="pnlUser"
    PopupDragHandleControlID="pnlPopupHeader"
    BackgroundCssClass="ModalPopup">
</ajaxToolkit:ModalPopupExtender>
<div id="pnlUser" style="display: none;height:600px;width:800px">
    <asp:Panel runat="Server" ID="pnlPopupHeader" CssClass="PopupHeader">
        User Search
    </asp:Panel>
    <iframe id="frmUserSearch" src="ModelUserSearch.aspx" scrolling="yes" style="height:100%;width:100%" frameborder="1">
    </iframe>
    <div style="display: none">
        <input id="btnOK" onclick="ok();" type="button" value="OK" />
        <input id="btnCancel" type="button" value="Cancel" />
    </div>
</div>

Button btnModelUser = new Button();
btnModelUser.ID = "btnModelUser_" + intAppIndex;
btnModelUser.Text = "Model User...";
btnModelUser.Click += new EventHandler(btnModelUser_Click);

UpdatePanel updModelUser = new UpdatePanel();
updModelUser.ID = "updModelUser_" + intAppIndex;
updModelUser.ContentTemplateContainer.Controls.Add(btnModelUser);

Table tblQuestions = new Table();
tblQuestions.ID = "tblQuestions_" + intAppIndex;

TableRow trModelUser = new TableRow();
trModelUser.ID = "trModelUser_" + intAppIndex;

TableCell tcModelUserButton = new TableCell();
tcModelUserButton.ID = "tcModelUserButton_" + intAppIndex;
tcModelUserButton.Controls.Add(updModelUser);

protected void btnModelUser_Click(object sender, EventArgs e)
{
    Button button = sender as Button;
    int intIndexUnderscore = button.ID.IndexOf("_");

    //Save index of applicaiton panel so popup knows where to update results
    hdnApplicationIndex.Value  = button.ID.Substring(intIndexUnderscore + 1);

    //Show the popup
    mpeUser.Show();
}