public void Visit(ArrayExpression list)
{
VisitComplex(list);
foreach (Expression item in list.Items)
Visit(item);
}
protected virtual void EvaluateItems(ArrayExpression Expression, object Collection, Type ItemType, IDeserializerHandler deserializer)
{
foreach (Expression item in Expression.Items)
{
item.ResultType = ItemType;
object itemResult = deserializer.Evaluate(item);
AddItem(Collection, itemResult);
}
}
protected virtual Expression GetExpression(IEnumerable Items, Type ItemType, JsonPath CurrentPath, ISerializerHandler serializer)
{
int index = 0;
ArrayExpression expression = new ArrayExpression();
foreach (object value in Items)
{
Expression itemExpr = serializer.Serialize(value, CurrentPath.Append(index));
if (value != null && !ReflectionUtils.AreEquivalentTypes(value.GetType(), ItemType))
{
itemExpr = new CastExpression(value.GetType(), itemExpr);
}
expression.Add(itemExpr);
index++;
}
return expression;
}
/// <summary>
/// Resolve a reference to an item within the collection
/// </summary>
/// <param name="refID">the reference to resolve</param>
/// <returns>the referenced expression</returns>
public void VisitListExpression(ArrayExpression expression)
{
Visit(typeof(ComplexExpressionBase), expression);
if (_expr != null)
return; // found it
int index = _refID.TopAsInt;
if (index < 0 || index >= expression.Items.Count)
{
throw new ArgumentOutOfRangeException("Reference to collection item out of range: " + _refID);
}
Expression expr = expression.Items[index];
Visit(expr);
}
protected virtual object ConstructCollection(ArrayExpression Expression, IDeserializerHandler deserializer)
{
object result = Activator.CreateInstance(Expression.ResultType);
return result;
}
/// <summary>
/// Parses a javascript array
/// </summary>
/// <returns></returns>
private ArrayExpression ParseCollection()
{
Token tok = ReadToken();
Debug.Assert(tok == LSquareToken);
ArrayExpression value = new ArrayExpression();
Expression item;
while (ReadAhead(CommaToken, RSquareToken, new ExpressionMethod(ParseExpression), out item))
{
value.Add(item);
}
return value;
}
/// <summary>
/// Serializes the data into a json array expression.
/// </summary>
/// <param name="data">the data to serialize</param>
/// <param name="currentPath">the current path to the data</param>
/// <param name="serializer">serializer instance to use to serialize list items</param>
/// <returns>a json array expression representation</returns>
public override Expression GetExpression(object data, JsonPath currentPath, ISerializerHandler serializer)
{
TypeData handler = Context.GetTypeHandler(data.GetType());
CollectionHandler collectionHandler = handler.GetCollectionHandler();
Type elemType = collectionHandler.GetItemType(handler.ForType);
int index = 0;
ArrayExpression expression = new ArrayExpression();
foreach (object value in collectionHandler.GetEnumerable(data))
{
Expression itemExpr = serializer.Serialize(value, currentPath.Append(index));
if (value != null && !ReflectionUtils.AreEquivalentTypes(value.GetType(), elemType))
{
itemExpr = new CastExpression(value.GetType(), itemExpr);
}
expression.Add(itemExpr);
index++;
}
return expression;
}
/// <summary>
/// Evaluates the items in the expression and assigns them to the collection using the builder
/// </summary>
/// <param name="expression">the expression to evaluate</param>
/// <param name="builder">builder used to build the collection</param>
/// <param name="itemType">the type of the collection's elements</param>
/// <param name="deserializer">deserializer instance to deserialize items</param>
/// <returns>evaluated collection object</returns>
protected virtual object EvaluateItems(ArrayExpression expression, ICollectionBuilder builder, Type itemType, IDeserializerHandler deserializer)
{
object result = null;
bool constructedEventSent = false;
try
{
result = builder.GetReference();
expression.OnObjectConstructed(result);
constructedEventSent = true;
}
catch
{
// this might fail if the builder's not ready
}
foreach (Expression item in expression.Items)
{
item.ResultType = itemType;
object itemResult = deserializer.Evaluate(item);
builder.Add(itemResult);
}
result = builder.GetResult();
if (!constructedEventSent)
expression.OnObjectConstructed(result);
return result;
}
/// <summary>
/// Constructs a builder used to build the deserialized collection
/// </summary>
/// <param name="collection">an existing collection object or null for a new collection</param>
/// <param name="list">the list expression</param>
/// <param name="itemType">the type of the items</param>
/// <returns>collection builder</returns>
protected virtual ICollectionBuilder ConstructBuilder(object collection, ArrayExpression list, out Type itemType)
{
Type listType = collection != null ? collection.GetType() : list.ResultType;
TypeData typeHandler = Context.GetTypeHandler(listType);
CollectionHandler collHandler = typeHandler.GetCollectionHandler();
itemType = collHandler.GetItemType(listType);
if (itemType == null)
throw new Exception("Null item type returned from " + collHandler.GetType() + " for Collection type: " + listType);
if (collection != null)
return collHandler.ConstructBuilder(collection);
else
return collHandler.ConstructBuilder(listType, list.Items.Count);
}
