/// <summary>
/// Constructs a new instance of the object represented by the expression.
/// </summary>
/// <param name="expression">json object expression</param>
/// <param name="deserializer">deserializer for deserializing constructor arguments if any</param>
/// <returns>constructed, but unpopulated object</returns>
protected virtual object ConstructObject(ObjectExpression expression, IDeserializerHandler deserializer)
{
ITypeData handler = Settings.Types[expression.ResultType];
// set the default type if none set
if (expression.ConstructorArguments.Count > 0)
{
// old way expects parameters in the constructor list
ResolveConstructorTypes(Settings, expression);
}
else
{
foreach (IPropertyData parameter in handler.ConstructorParameters)
{
int propLocation = expression.IndexOf(parameter.Alias);
if (propLocation >= 0)
{
Expression arg = expression.Properties[propLocation].ValueExpression;
arg.ResultType = parameter.PropertyType;
expression.ConstructorArguments.Add(arg);
expression.Properties.RemoveAt(propLocation);
}
else
{
expression.ConstructorArguments.Add(new NullExpression());
}
}
}
object[] args = new object[expression.ConstructorArguments.Count];
for (int i = 0; i < args.Length; i++)
{
Expression carg = expression.ConstructorArguments[i];
if (i < handler.ConstructorParameters.Count && handler.ConstructorParameters[i].HasConverter)
{
TypeConverterExpressionHandler converterHandler = (TypeConverterExpressionHandler)Settings.ExpressionHandlers.Find(typeof(TypeConverterExpressionHandler));
args[i] = converterHandler.Evaluate(carg, deserializer, handler.ConstructorParameters[i].TypeConverter);
}
else
{
args[i] = deserializer.Evaluate(carg);
}
}
object result = handler.CreateInstance(args);
expression.OnObjectConstructed(result);
return(result);
}
protected virtual void EvaluateItem(object existingObject, IDeserializerHandler deserializer, ITypeData typeHandler, KeyValueExpression Item)
{
// evaluate the item and let it assign itself?
IPropertyData hndlr = typeHandler.FindPropertyByAlias(Item.Key);
if (hndlr == null)
{
switch (this.Settings.MissingPropertyAction)
{
case MissingPropertyOptions.Ignore:
return;
case MissingPropertyOptions.ThrowException:
throw new Exception(string.Format("Could not find property {0} for type {1}", Item.Key, typeHandler.ForType));
default:
throw new InvalidOperationException("Unhandled MissingPropertyAction: " + this.Settings.MissingPropertyAction);
}
}
if (hndlr.Ignored)
{
switch (Settings.IgnoredPropertyAction)
{
case IgnoredPropertyOption.Ignore:
return;
case IgnoredPropertyOption.SetIfPossible:
if (!hndlr.CanWrite)
{
return;
}
break;
case IgnoredPropertyOption.ThrowException:
throw new Exception(string.Format("Can not set property {0} for type {1} because it is ignored and IgnorePropertyAction is set to ThrowException", Item.Key, typeHandler.ForType));
}
}
Expression valueExpression = Item.ValueExpression;
valueExpression.ResultType = hndlr.PropertyType;
object result = null;
TypeConverterExpressionHandler converterHandler = null;
IJsonTypeConverter converter = null;
if (hndlr.HasConverter)
{
converterHandler = (TypeConverterExpressionHandler)Settings.ExpressionHandlers.Find(typeof(TypeConverterExpressionHandler));
converter = hndlr.TypeConverter;
}
if (!hndlr.CanWrite)
{
result = hndlr.GetValue(existingObject);
if (converterHandler != null)
{
converterHandler.Evaluate(valueExpression, result, deserializer, converter);
}
else
{
deserializer.Evaluate(valueExpression, result);
}
}
else
{
if (hndlr.HasConverter)
{
hndlr.SetValue(existingObject, converterHandler.Evaluate(valueExpression, deserializer, converter));
}
else
{
hndlr.SetValue(existingObject, deserializer.Evaluate(valueExpression));
}
}
}
