How to set Invoice ID in plugin pre-operation in Dynamics CRM 2016?

Question

I am using following code snippet to set the Invoice ID of Invoices in plugin pre-operation. But I am unable to do so. I want to seek your kind suggestion to set the value.

Update

QueryExpression qe = new QueryExpression
            {
                EntityName = "invoice",
                ColumnSet = new ColumnSet("salesorderid", "invoicenumber"),
                Criteria = new FilterExpression
                {
                    Conditions = {
                                    new ConditionExpression("salesorderid",ConditionOperator.Equal,orderId)
                                }
                }
            };

            EntityCollection ec = service.RetrieveMultiple(qe);

if (ec.Entities.Count == 0) 
            {
                string orderName = generateInvoiceID(service, orderId);

                foreach (Entity id  in ec.Entities)
                {
                    id.Attributes["invoicenumber"] = Convert.ToInt32(orderName) + 01;
                }

            }

Answer 1

Looking at the snippet looks like you have the plugin registered on "SalesOrder" entity and you are trying to update invoice entity, so it does not matter if it is a pre-op or a post-op, you would need to explicitly call IOrganizationService.Update

       var qe = new QueryExpression
        {
            EntityName = "invoice",
            ColumnSet = new ColumnSet("salesorderid", "invoicenumber"),
            Criteria = new FilterExpression
            {
                Conditions =
                {
                    new ConditionExpression("salesorderid", ConditionOperator.Equal, orderId)
                }
            }
        };

       var ec = service.RetrieveMultiple(qe);
       var orderName = generateInvoiceID(service, orderId);

        foreach (var entity in ec.Entities)
        {
            var invoice = new Entity("invoice") { Id = entity.Id };
            invoice.Attributes.Add("invoicenumber", Convert.ToInt32(orderName) + 01);
            service.Update(invoice); //call the update method.
        }