form validation before direct click event fire

问题:

I have a button,I want to form validation(client side) before direct click event fire.I tryed lots of way but failed.

** I already set textbox like this.

 <ext:TextField ID="Ad" runat="server" FieldLabel="Dem ad" Flex="1" AllowBlank="false" CausesValidation="true"> </ext:TextField>

but still fire direct even before textbox checking

---

<ext:Button ID="Button1" runat="server" Text="save" Icon="Disk">
                                  <DirectEvents>

                                    <Click OnEvent="Dem">
                                        <Confirmation ConfirmRequest="true"  Title="Title" Message="are u sure you want to update..." />

                                    </Click>

                                </DirectEvents>


                            </ext:Button>

回答1:

There is a few options.

1. You can return false from a DirectEvent's Before handler or from the same Listener.

   protected void Submit(object sender, DirectEventArgs e) { X.Msg.Alert("Submit", "Submitted").Show(); }

   Ext.NET v2 Example

       <ext:FormPanel ID="FormPanel1" runat="server">
           <Items>
               <ext:TextField runat="server" AllowBlank="false" />
           </Items>
       </ext:FormPanel>
   
       <ext:Button runat="server" Text="Submit">
           <%--<Listeners>
               <Click Handler="return false;" /> it has the same effect as returning false from a DirectEvent's Before.
           </Listeners>--%>
           <DirectEvents>
               <Click OnEvent="Submit" Before="return App.FormPanel1.isValid();" />
           </DirectEvents>
       </ext:Button>
   </form>
   

2. Another approach is using FormBind. It automatically disables a component if a FormPanel is invalid. A component should belong to a FormPanel.

   protected void Submit(object sender, DirectEventArgs e) { X.Msg.Alert("Submit", "Submitted").Show(); }

   Ext.NET v2 Example

       <ext:FormPanel ID="FormPanel1" runat="server" Width="200">
           <Items>
               <ext:TextField runat="server" AllowBlank="false" />
           </Items>
           <Buttons>
               <ext:Button runat="server" Text="Submit" FormBind="true">
                   <DirectEvents>
                       <Click OnEvent="Submit" />
                   </DirectEvents>
               </ext:Button>
           </Buttons>
       </ext:FormPanel>
   </form>
   

3. You can listen a FormPanel's ValidityChange event to apply some custom actions.