Clever Geek Handbook

What do you suspect when ASP.NET ignores CustomValidator?

This is a code maintenance issue as a code issue, but I have a WebForm that no longer checks its CustomValidator. It worked when I last touched the code over a year ago, but now it doesn't work anymore when the user requested some changes ...

The WebForm contains a drop-down list of data with a default of "- All -" with String.Empty as the value. When the user clicks the submit button, the validator must check that the dropdown value is not equal to String.Empty. I have set breakpoints in client validation code and server validation code, but not fire.

Where would you start looking? What are the usual suspects? I have, of course, compared my working copy with one that is under source control, but nothing seems suspicious.

It's important just in case, here's my code:

<asp:DropDownList ID="_AssessmentDropDown" runat="server" DataSourceID="_AssessmentsData" CausesValidation="true" AutoPostBack="false"
    DataTextField="AssessmentName" DataValueField="AssessmentName" OnDataBound="_HandleAssessmentsBound">
</asp:DropDownList>
<asp:CustomValidator ID="_AssessmentValidator" runat="server" ClientValidationFunction="_HandleValidateAssessment_Client"
    ControlToValidate="_AssessmentDropDown" ErrorMessage="* You must select an Assessment."
    OnServerValidate="_HandleValidateAssessment" />
<asp:ObjectDataSource ID="_AssessmentsData" runat="server"
    OldValuesParameterFormatString="original_{0}" SelectMethod="GetData"
    TypeName="DataTableAdapters.GET_GRADE_ASSESSMENTSTableAdapter">
    <SelectParameters>
      <asp:ControlParameter Name="GRADECODE" ControlID="_GradeCodeDropDown" PropertyName="SelectedValue" />
    </SelectParameters>
</asp:ObjectDataSource>
0


source to share


5 answers


I notice a couple of problems



  • I don't think you need CausesValidation = true if AutoPostBack is set to false
  • You are not using validation groups, so this cannot be the reason
  • Why not use RequiredFieldValidator?
  • If you want to activate validation for empty fields, set the ValidateEmptyText property to true
+5


source


CustomValidator does not fire if the control it validates is empty, so the CustomValidator parameter must always be set to RequiredFieldValidator



+1


source


Some troubleshooting steps:

  • Is this the only validator on the form?
  • Is on-page validation enabled?
  • Is validation allowed for the target control?
  • Is the validator enabled?
0


source


I would take a serious look at ValidationGroup.

If something is left outside the group, it will no longer be checked. If not, make sure you don't have a javascript error (client side) and that the method that is "OnServerValidate" has a breakpoint inside.

0


source


Is the validator in the same validator group as the submit button?

0


source






More articles:


All Articles