Dry data: StoredProcedure class (aka "the parameter sponge")

StoredProcedure.cs

public class StoredProcedure
{
    private readonly DbProviderFactory _dpf;
    private readonly DbCommand _sp;

    public StoredProcedure(DbCommand sp, DbProviderFactory dpf)
    {
        _sp = sp;
        _dpf = dpf;
    }

    public StoredProcedure this[string parameterName, 
      object value, int? size = null, DbType? type = null]
    {
        get { return AddParameter(parameterName, value, size, type); }
    }

    public StoredProcedure AddParameter(string parameterName, 
      object value, int? size = null, DbType? type = null)
    {
        var p = _dpf.CreateParameter();
        if (p != null)
        {
            p.ParameterName = parameterName;
            p.Value = value;
            if (size.HasValue)
            {
                p.Size = size.Value;
            }
            if (type.HasValue)
            {
                p.DbType = type.Value;
            }
            _sp.Parameters.Add(p);
        }
        return this;
    }
}