Stored procedure, empty parameters

Question

I am working in c #, wpf with mvvm and a stored procedure in sql server 2008.

I have a problem when sending the values ​​to the function where the stored procedure is executed, I get then from a form, where it can leave some fields empty. But these are objects of a class, then to access them should not be null. I leave the code.

        public IEnumerable<Model.AsuntoModel> GetBusqueda(Model.PrioridadModel prioridad, Model.StatusAsuntoModel statusasunto, Model.DestinatarioModel destinatario, Model.SignatarioModel signatario, DateTime rangofecha, DateTime referenciadocumento)
    {
        ObservableCollection<Model.AsuntoModel> Busqueda = new ObservableCollection<Model.AsuntoModel>();
        using (var entity = new GestorDocumentEntities())
        {

            try 
             {
                 entity.GetAsuntos(prioridad.IdPrioridad, statusasunto.IdStatusAsunto, destinatario.IdDestinatario, signatario.IdSignatario, referenciadocumento).ToList().ForEach(p =>
                 {
                     Busqueda.Add(new Model.AsuntoModel()
                     {
                         IdAsunto = p.IdAsunto,
                         FechaCreacion = (DateTime)p.FechaCreacion,
                         FechaRecibido = (DateTime)p.FechaRecibido,
                         FechaDocumento = (DateTime)p.FechaDocumento,
                         Titulo = p.Titulo,
                         Descripcion = p.Descripcion,
                         Alcance = p.Alcance,
                         IdUbicacion = (long)p.IdUbicacion,
                         Ubicacion = new Model.UbicacionModel()
                         {
                             UbicacionName = p.CAT_UBICACION.UbicacionName
                         },
                         IdInstruccion = (long)p.IdInstruccion,
                         Instruccion = new Model.InstruccionModel()
                         {
                             InstruccionName = p.CAT_INSTRUCCION.InstruccionName
                         },
                         IdPrioridad = (long)p.IdPrioridad,
                         Prioridad = new Model.PrioridadModel()
                         {
                             PrioridadName = p.CAT_PRIORIDAD.PrioridadName
                         },
                         IdStatusAsunto = p.IdStatusAsunto,
                         StatusAsunto = new Model.StatusAsuntoModel()
                         {
                             StatusName = p.CAT_STATUS_ASUNTO.StatusName
                         },
                         FechaVencimiento = p.FechaVencimiento,
                         Folio = p.Folio
                     });
                 }); 

             }
            catch (Exception)
            {
                ;
            }
        }
        return Busqueda;
    }

Answer 1

Here's one of many solutions.

You simply make you SQL parameters nullable by giving them a default value.

E.g :

@ParamA = null
@ParamB = null
etc..

Then you manage this on the SQL side to see how many you've received.
This way, your query will have a valu (in this case null) for you parameters if you don't supply any. You can then test it like :

IF @ParamA IS NULL
BEGIN
-- You didn't give that param.
END
ELSE
-- You gave a param

Answer 2

Your SP can be coded to treat NULL parms as ANY.

select *
from table
where (table.col = @COL or @COL IS NULL)
and (table.col2 = @COL2 or @COL2 IS NULL)