Double server validate with CustomValidator in RadGrid

[Louis]

Why when I'm using asp.net CustomValidator inside Insert/Edit ItemTemplate column of my RadGrid, the ServerValidate method is fired two times ?

I'm using telerik version 2015.3.930.45

Example:

Asp.net

 

<telerik:GridTemplateColumn UniqueName="ProductName" HeaderText="Product">
   <ItemTemplate><%# Eval("ProductName") %></ItemTemplate>
   <EditItemTemplate>
      <asp:TextBox Id="ProductNameText" Text='<%# Eval("ProductName") %>' runat="server"/>
      <asp:CustomValidator ID="ProductNameValidator" ControlToValidate="ProductNameText" Text="*" ErrorMessage="*" OnServerValidate="ProductNameValidator_OnServerValidate" runat="server"/>
   </EditItemTemplate>
</telerik:GridTemplateColumn>

 

C#

protected void ProductNameValidator_OnServerValidate(object source, ServerValidateEventArgs args)
{
   var newProductName = args.Value;
   args.IsValid = _myProducts.All(x => x.ProductName != newProductName);
}

 ​

[Louis]

Sorry for the confusion about my first sentence.

My question is, why "OnServerValidate" method is fired two times, when customValidator are inside RadGrid ?

[Maria Ilieva]

Hello Louis,

I revise the presented column declaration and it looks absolutely correct without anything obvious that may lead to the described behavior. You can revise the online demo below where the OnServerValidate fires correctly and see what the difference in your case is:
http://demos.telerik.com/aspnet-ajax/grid/examples/data-editing/validation/defaultcs.aspx
​

Regards,
Maria Ilieva
Telerik

[Louis]

After a review of your exemple, it's also fired CustomValidation twice after user click on the "Insert"/"Update" button.

 It's seem to be a asp.net webform bugs with CustomValidator include inside a Templated List control.

 The way we correct this "double validation" is to override Page.Validate()

private bool _wasValidated;
protected override Validate() {
   if(!_wasValidated)
      base.Validate();
}

Thanks for you quick response to my thread

[Louis]

in fact...

 

private bool _wasValidated;
protected override Validate() {
   if(!_wasValidated) {
      base.Validate();
      _wasValidated - true;
   }
}

[Maria Ilieva]

Hi,

Thank you for sharing your findings. I'm sure this will help other users that are facing the same behavior.

Regards,
Maria Ilieva
Telerik