// takes a BamlCollectionHolder and its context and sets the value of the holder's collection to be
// either the default collection instantiated by the holder's constructor or a newly created
// collection created based on the expected type.
// *** Used when we do not have an explicit tag.
private void InitPropertyCollection(BamlCollectionHolder holder, ReaderContextStackData context)
{
// this method should only be called to initialize the collection
Debug.Assert (holder.Collection == null);
if (context.ContextType == ReaderFlags.PropertyArray)
{
// arrays are a little different than other collections, because we wrap them in an array extension.
// Here we create an array extension and assign the element type based on the property.
ArrayExtension arrayExt = new ArrayExtension();
arrayExt.Type = context.ExpectedType.GetElementType();
holder.Collection = arrayExt;
}
else if (holder.DefaultCollection != null)
{
// if we the property getter returned a default value, then we use that collection to insert
// as the property's collection.
holder.Collection = holder.DefaultCollection;
}
else
{
ThrowException(SRID.ParserNullPropertyCollection, holder.PropertyDefinition.Name);
}
context.ExpectedType = null; // Don't want to receive any other values
}
// Start of an IList or IEnumerable property. Get the IList value from the parent
// object and store it on the reader stack, so that records encountered under this
// list can be added to it.
protected virtual void ReadPropertyIListStartRecord(
BamlPropertyIListStartRecord bamlPropertyIListStartRecord)
{
short attributeId = bamlPropertyIListStartRecord.AttributeId;
object parent = GetCurrentObjectData();
BamlCollectionHolder holder = new BamlCollectionHolder(this, parent, attributeId);
Type expectedType = holder.PropertyType;
// If the property does not implement IList or IAddChild, see if the parent
// (which is the current object on the top of the stack) implements IAddChild
// and try that for adding items later on. First look at defined propertyType
// obtained from the DP or PropertyInfo. If that doesn't work, then look at
// the actual type of object retrieved using GetValue.
ReaderFlags flags = ReaderFlags.Unknown;
if (typeof(IList).IsAssignableFrom(expectedType))
{
flags = ReaderFlags.PropertyIList;
}
else if (BamlRecordManager.TreatAsIAddChild(expectedType))
{
flags = ReaderFlags.PropertyIAddChild;
holder.Collection = holder.DefaultCollection;
holder.ReadOnly = true;
}
else if (typeof(IEnumerable).IsAssignableFrom(expectedType) &&
(BamlRecordManager.AsIAddChild(GetCurrentObjectData())) != null)
{
flags = ReaderFlags.PropertyIAddChild;
holder.Collection = CurrentContext.ObjectData;
holder.ReadOnly = true;
expectedType = CurrentContext.ObjectData.GetType();
}
else
{
// if we reached this case, then we had a read-only IEnumerable property
// under a non-IAddChild element. Throw an exception
ThrowException(SRID.ParserReadOnlyProp, holder.PropertyDefinition.Name);
}
PushContext(flags | ReaderFlags.CollectionHolder, holder, expectedType, 0);
// Set the name of the property into the context
CurrentContext.ElementNameOrPropertyName = holder.AttributeName;
}
// Start of an IDictionary encountered. Set up the BamlDictionaryHolder on the reader
// stack so that items can be added to it.
protected virtual void ReadPropertyIDictionaryStartRecord(
BamlPropertyIDictionaryStartRecord bamlPropertyIDictionaryStartRecord)
{
short attributeId = bamlPropertyIDictionaryStartRecord.AttributeId;
object parent = GetCurrentObjectData();
BamlCollectionHolder holder = new BamlCollectionHolder(this, parent, attributeId);
PushContext(ReaderFlags.PropertyIDictionary | ReaderFlags.CollectionHolder, holder, holder.PropertyType, 0);
// Set the name of the property into the context
CurrentContext.ElementNameOrPropertyName = holder.AttributeName;
}
// Read the start of an array property. Set up the BamlArrayHolder that is needed to
// hold array contents.
protected void ReadPropertyArrayStartRecord(BamlPropertyArrayStartRecord bamlPropertyArrayStartRecord)
{
short attributeId = bamlPropertyArrayStartRecord.AttributeId;
object parent = GetCurrentObjectData();
BamlCollectionHolder holder = new BamlCollectionHolder(this, parent, attributeId, false /*needDefault*/);
if (!holder.PropertyType.IsArray)
{
ThrowException(SRID.ParserNoMatchingArray, GetPropertyNameFromAttributeId(attributeId));
}
Debug.Assert(!holder.ReadOnly); // this is being checked in XamlReaderHelper, just assert
PushContext(ReaderFlags.PropertyArray | ReaderFlags.CollectionHolder, holder, holder.PropertyType, 0);
// Set the name of the property into the context
CurrentContext.ElementNameOrPropertyName = holder.AttributeName;
}