Validation of Publish button

I want that publish/unpublish command will be performed only if the survey have at least one question.
If the publish button pressed in the zero -question line - the user must get the red warning message:

You cannot publish survey with zero questions


But how to do it? The validate function cannot receive any additional parameters except

object sender, ServerValidateEventArgs e

And we cant even figure out which repeater item sended the command since the publish button not requires any item checkboxses to be checked.

Custom validator:

<asp:CustomValidator ID="CustomValidator2" runat="server"

ErrorMessage="You cannot publish survey with zero questions"

ValidationGroup="zeroQuestions" Display="Dynamic" OnServerValidate="IsZeroQuestions">

</asp:CustomValidator>

It raises the server-validation function IsZeroQuestions
how can this function "know" what the questions number of line(Repeater Item) whose raised it?



Well, it means i need to change the way the Publish/Unpublish button working:
From now it will work this way:

protected void PublishThisSurvey(object sender, RepeaterCommandEventArgs e)

    {

        RepeaterItem ri = Repeater1.Items[e.Item.ItemIndex];

        CheckBox chkBox = (CheckBox)ri.FindControl("CheckBox1");

        chkBox.Checked = true; 

        Validate("zeroQuestions");

        if (!Page.IsValid)

        {

        CustomValidator2.ErrorMessage = "Cannot publish this

            survey with zero questions";

            chkBox.Checked = false;

            return;

        }

        HiddenField hf;

        hf = (HiddenField)ri.FindControl("surveyID");

        int surveyID = Convert.ToInt32(hf.Value);

HiddenField isPhf = (HiddenField)ri.FindControl("IsPublished_hf");

        bool bIsPublished = Convert.ToBoolean(isPhf.Value);

      

        //turn upside

        bIsPublished = (bIsPublished) ? false : true;

        clsDataAccess myclass = new clsDataAccess();

        myclass.UpdateSurveyPublished(surveyID, bIsPublished);

        Repeater1.DataBind();

    }

and the trigger will be ItemCommand of Repeater:

<asp:Repeater ID="Repeater1" runat="server"

DataSourceID="SurveysSqlDataSource" OnItemCommand="PublishThisSurvey">