Modal Popup: Will not access event handler in code behind prior to showing modal popup.

I have an AJAX modal popup that is tied to a 'Continue' button on a ASP.NET page. The issue is that I have required field validators with messages next to controls that need to be displayed if information is missing. Right now, the AJAX modal shows upon pressing 'Continue' regardless of if infomration is missing on the page. I put a break point in the event handler for the 'Continue' button and it never even gets hit.

How can I intervene and NOT show the modal popup untilall required field validators are satisfied?

if (Page.IsValid)
modalDialogExtender.Show()
else
//do nuthin

Yes and No. When pressing the button that is the TargetControlID of the modal box, the button event handler of that TargetID is is never reached prior to the modal being displayed. That is the No. However, I added a second hidden control as the TargetControlD that can not be accessed from the page to satisfy the modal's proerties. Then when my 'Continue' button is pressed, Yes, the code you provided works and is hit and the modal is shown programatically (assuming PageIsValid = True).

Thank you for the response.

Modalpopup - Web Service Call Failed

My web service works great when I call it outside of the modalpopupextender. However, I can't seem to access the asmx page at all when using the modalpopup dynamic properties. I keep receiving errors stating both "web service call failed: 12030" & "web service call failed: 500" randomly. What am I missing here? Any help you can lend to my problem would be greatly appreciated!

<ajaxToolkit:ToolkitScriptManagerID="ScriptManager1"runat="server">
<Services>
<asp:ServiceReferencepath="~/GetCity.asmx"/>
</Services>
</ajaxToolkit:ToolkitScriptManager>

<asp:GridViewID="GridView1"runat="server"DataKeyNames="FILENAME"AutoGenerateSelectButton="True">
<Columns>
<asp:TemplateField>
<ItemTemplate>
<asp:linkButtonID="hlnkOrders"runat="server">Selectlnk</asp:linkButton>
<ajaxToolkit:ModalPopupExtenderID="ModalPopupExtender3"runat="server"
OKControlID="btnOK"
PopupControlID="Panel3"
TargetControlID="hlnkOrders"
DynamicServicePath="GetCity.asmx"
DynamicServiceMethod="LookupCityCode"
DynamicControlID="lblhidden"
DynamicContextKey='<%=eval("FILENAME") %>'
BackgroundCssClass="modal"
DropShadow="true">
</ajaxToolkit:ModalPopupExtender>
</ItemTemplate>
</asp:TemplateField>
</Columns>
<AlternatingRowStyleBackColor="#FFFFC0"BorderColor="#004000"BorderWidth="1px"/>
</asp:GridView>

<asp:Panelrunat="server"ID="Panel3"BackColor="AliceBlue">
<asp:LabelID="lblHidden"runat="server"></asp:Label><br/><br/>
<asp:Buttonrunat="server"ID="btnOK"Text="OK"/>
</asp:Panel>

Imports System.Web.Script.Services.ScriptServiceAttribute
Imports System.Web.Script.Services.ScriptMethodAttribute

<WebService(Namespace:="http://tempuri.org/")> _
<WebServiceBinding(ConformsTo:=WsiProfiles.BasicProfile1_1)> _
<Global.Microsoft.VisualBasic.CompilerServices.DesignerGenerated()> _
PublicClass GetCity

Inherits System.Web.Services.WebService

Private strUserNameAsString =""
Private strServerNameAsString =""
Private strPasswordAsString =""
Private wAttachmentPathAsString =""

<WebMethod()> _
PublicFunction LookupCityCode(ByVal contextKeyAsString)AsString

'do some stuff
ReadExcelOrder(wattachmentPath & contextKey)
LoadParameters()

End Function

PrivateFunction ReadExcelOrder(ByVal FileNameAsString)AsString

'do some stuff

End Function

PrivateSub LoadParameters()

'do some stuff

End Sub

I'll answer my own question here. Once I added the property System.Web.Script.Services.ScriptService to the webservice, it works!

<WebService(Namespace:="http://tempuri.org/")> _
<System.Web.Script.Services.ScriptService()> _
<WebServiceBinding(ConformsTo:=WsiProfiles.BasicProfile1_1)> _
<Global.Microsoft.VisualBasic.CompilerServices.DesignerGenerated()> _
PublicClass GetCity

Even after adding

[System.Web.Script.Services.ScriptService]

 to my service it is not working. Please help