Recently I had to validate some filter selections on a report in Business Central and found out it was not so straight forward to do. What happened when using the trigger OnPreDataItem() or trigger OnPreReport() triggers was that I was able to validate the filter selections by user but the user experience was not optimal since the selection page closed when the validation error occured.

What I came up with was using the trigger OnQueryClosePage(CloseAction: Action): Boolean trigger on the requestpage itself.

Here’s the sample report:

report 50100 Customers
{
    UsageCategory = ReportsAndAnalysis;
    ApplicationArea = All;
    DefaultRenderingLayout = LayoutName;
    Caption = 'Customer Report';
    dataset
    {
        dataitem(Customer; Customer)
        {
            RequestFilterFields = "Gen. Bus. Posting Group", "Customer Posting Group";
            column(Name; Name)
            {

            }
            column(Amount; Amount)
            {

            }
        }
    }

    requestpage
    {
        layout
        {

        }
        trigger OnQueryClosePage(CloseAction: Action): Boolean
        begin
            if CloseAction = Action::Cancel then
                exit
            else begin
                ValidateFilter(Customer.GetFilter("Gen. Bus. Posting Group"), Customer.FieldCaption("Gen. Bus. Posting Group"));
                ValidateFilter(Customer.GetFilter("Customer Posting Group"), Customer.FieldCaption("Customer Posting Group"));
            end;
        end;

    }
    rendering
    {
        layout(LayoutName)
        {
            Type = RDLC;
            LayoutFile = 'report.rdlc';
        }
    }

    local procedure ValidateFilter(Filter: Text; FieldCaption: Text)
    var
        ErrFieldValueMissingInSelection: Label 'Please select filter for field: %1';
    begin
        if Filter = '' then
            Error(ErrFieldValueMissingInSelection, FieldCaption);
    end;
}

Theres a generic procedure local procedure ValidateFilter(Filter: Text; FieldCaption: Text) that you can pass on any field filter and value and it will validate that and show error before the report is run:

I think this way the user experience is quite good for validating the request page fields before the report is run.