protected virtual BaseCriteria Visit(BaseCriteria criteria)
{
if (Object.ReferenceEquals(null, criteria))
{
return(null);
}
if (criteria is Criteria)
{
return(VisitCriteria((Criteria)criteria));
}
if (criteria is BinaryCriteria)
{
return(VisitBinary((BinaryCriteria)criteria));
}
if (criteria is UnaryCriteria)
{
return(VisitUnary((UnaryCriteria)criteria));
}
if (criteria is ValueCriteria)
{
return(VisitValue((ValueCriteria)criteria));
}
if (criteria is ParamCriteria)
{
return(VisitParam((ParamCriteria)criteria));
}
throw new Exception(String.Format("Unhandled criteria type: '{0}'", criteria.GetType().Name));
}
/// <summary>
/// Visits the specified criteria.
/// </summary>
/// <param name="criteria">The criteria.</param>
/// <returns></returns>
/// <exception cref="Exception">Criteria type is unkown.</exception>
protected virtual BaseCriteria Visit(BaseCriteria criteria)
{
if (criteria is null)
{
return(null);
}
if (criteria is Criteria crit)
{
return(VisitCriteria(crit));
}
if (criteria is BinaryCriteria binary)
{
return(VisitBinary(binary));
}
if (criteria is UnaryCriteria unary)
{
return(VisitUnary(unary));
}
if (criteria is ValueCriteria value)
{
return(VisitValue(value));
}
if (criteria is ParamCriteria prm)
{
return(VisitParam(prm));
}
throw new InvalidProgramException(string.Format("Unhandled criteria type: '{0}'", criteria.GetType().Name));
}
private void ToJson(JsonWriter writer, BaseCriteria criteria, JsonSerializer serializer)
{
if (criteria is null ||
criteria.IsEmpty)
{
writer.WriteNull();
return;
}
if (criteria is ValueCriteria valueCriteria)
{
var value = valueCriteria.Value;
if (value != null && value is IEnumerable && !(value is string))
{
// make sure that first value in array won't be recognized as a operator
// while deserializing (e.g. if values are [">", "a", "b"], serialize them
// as [[">", "a", "b"]] so that the first > won't be recognized as GE operator.
writer.WriteStartArray();
serializer.Serialize(writer, value);
writer.WriteEndArray();
return;
}
serializer.Serialize(writer, value);
return;
}
if (criteria is ParamCriteria prm)
{
writer.WriteStartArray();
serializer.Serialize(writer, prm.Name);
writer.WriteEndArray();
return;
}
if (criteria is Criteria crit)
{
writer.WriteStartArray();
serializer.Serialize(writer, crit.Expression);
writer.WriteEndArray();
return;
}
if (criteria is UnaryCriteria unary)
{
writer.WriteStartArray();
writer.WriteValue(OperatorToKey[(int)unary.Operator]);
ToJson(writer, unary.Operand, serializer);
writer.WriteEndArray();
return;
}
if (criteria is BinaryCriteria binary)
{
writer.WriteStartArray();
ToJson(writer, binary.LeftOperand, serializer);
writer.WriteValue(OperatorToKey[(int)binary.Operator]);
ToJson(writer, binary.RightOperand, serializer);
writer.WriteEndArray();
return;
}
throw new JsonSerializationException(string.Format("Can't serialize criteria of type {0}", criteria.GetType().FullName));
}
