/// <summary>
/// Check an XmlElement to see if it includes a specific "Type" attribute. If so, return
/// the actual Type associated with that attribute's value.
/// </summary>
/// <param name="_xml">The XmlElement containing the field's information</param>
/// <param name="_defaultType">
/// If there is no Type attribute, then return this value as the "default"
/// </param>
/// <returns>
/// NULL if no Type attribute was found, or the Type object corresponding the value of
/// the Type attribute
/// </returns>
/// <exception cref="InvalidOperationException">
/// Thrown if there is a Type attribute, but that attribute's value cannot be turned
/// into a Type object.
/// </exception>
private Type GetTypeFromXmlOrDefault(XmlElement _xml, Type _defaultType)
{
var sType = XmlExtensions.GetAttributeValue(_xml, m_context.TypeAttributeName);
if (sType == null) // There is no explicit Type specifier (XmlAttribute)
{
return(_defaultType);
}
var explicitType = Lib.BetterGetType(sType, true);
if (explicitType == null)
{
// The XML had an explicit Type, but that Type couldn't be found. So... If we
// are trying to deserialize a Type that uses EntitySemantics, we assume that
// the destination Type is sufficient to figure out what to deserialize. If the
// destination Type is wholly inadequate to "receive" the data in the XML, the
// application is at fault. For Entities, this type of mismatch is OK.
if (CEntityTypeData.UsesEntitySemantics(_defaultType))
{
return(_defaultType);
}
// However, if this isn't using EntitySemantics, then throw an exception as the
// Type is unknown.
throw new XDeserializationError("An Attribute was found for an Explicit Type, but it could not be turned into a Type: " + sType);
}
return(explicitType);
}
/// <summary>
/// Using childNodes from an element, deserialize an array by deserializing the
/// individual elements into the array elements.
/// </summary>
/// <param name="_xml">
/// The XML parent node containing the array elements as childNodes
/// </param>
/// <param name="_arrayHelper">The ArrayDeserializationHelper</param>
private void DeserializeArrayFromElements(XmlElement _xml, CArrayDeserializationHelper _arrayHelper)
{
foreach (XmlNode node in _xml.ChildNodes)
{
if (!(node is XmlElement elem))
{
throw new XDeserializationError(node.NodeType.ToString() +
" was the nodetype found (instead of XmlElement) as a child of the array's XML");
}
int[] indicies = null;
var sIndex = XmlExtensions.GetAttributeValue(elem, m_context.ArrayIndexAttributeName);
if (sIndex != null)
{
indicies = sIndex.Split(',').Select(s => int.Parse(s)).ToArray();
}
if (indicies != null && indicies.Length > 0)
{
_arrayHelper.SetIndicies(indicies);
}
var obj = FrameworkDeserialize(elem, _arrayHelper.ElementType);
_arrayHelper.Add(obj);
}
}
/// <summary>
/// The framework will deserialize the object. No more surrogates or other "exceptional"
/// behaviour.
/// </summary>
/// <param name="_xml"></param>
/// <param name="_type"></param>
/// <param name="_workingObject"></param>
private void HandleDeserialization(XmlElement _xml, Type _type, CWorkingObject _workingObject)
{
// Strings are really easy- just return the "InnerText"
if (_type == TYPEOF_STRING)
{
_workingObject.Set(Environment.ExpandEnvironmentVariables(_xml.InnerText));
}
// Primitives are also pretty easy, only because of the "Convert" class
else if (_type.IsPrimitive)
{
_workingObject.Set(Convert.ChangeType(_xml.InnerText, _type));
}
// Check for an Array
else if (_type.IsArray || XmlExtensions.HasAttribute(_xml, m_context.ArrayAttributeName))
{
DeserializeArray(_xml, _type, _workingObject);
}
else if (_type.IsEnum)
{
_workingObject.Set(Enum.Parse(_type, _xml.InnerText, false));
}
else // Handle ref-type fields and base classes.
{
DeserializeReferenceType(_xml, _type, _workingObject);
}
}
/// <summary>
/// Check the easiest forms of deserialization- Null and RefTo an object already
/// deserialized.
/// </summary>
/// <param name="_xml">The XML that's being deserialized</param>
/// <param name="_workObj">
/// The Object that was deserialized (when the return value is TRUE)
/// </param>
/// <returns>
/// TRUE means that the _workObj parameter contains valid data and nothing further
/// should be done, FALSE means that no deserialization was performed.
/// </returns>
private bool CheckNullAndReference(XmlElement _xml, CWorkingObject _workObj)
{
// Check the XML to see if this is a NULL object reference. If it is, then return
// TRUE.
if (XmlExtensions.HasAttribute(_xml, m_context.NullAttributeName))
{
return(true);
}
// Check the XML to see if its referring to some other object.
var referTo = XmlExtensions.GetAttributeValue(_xml, m_context.ReferToAttributeName);
if (referTo != null) // There was a reference to another object, so handle it and return that other object.
{
// Check the table for the RefID to get the object. The reference must be in the
// table already because forward-looking references are not supported.
if (!m_references.TryGetValue(referTo, out var obj))
{
throw new XUnknownReference("All object-references must be to backward-defined objects. The RefID " + referTo + " has not been defined yet.");
}
_workObj.Set(obj);
return(true);
}
// Check to see if this element is associating the XML with a reference ID
var refId = XmlExtensions.GetAttributeValue(_xml, m_context.ReferenceIdAttributeName);
if (refId != null)
{
_workObj.SetRefInfo(this, refId);
}
return(false);
}
/// <summary>
/// Given information about the current state, create an ArrayDeserializationHelper to
/// help with the deserialization process
/// </summary>
/// <param name="_xml">The XML containing the Array information</param>
/// <param name="_type">The Type of the array expected</param>
/// <param name="_workingObject">
/// A "Working Object", likely from a surrogate that didn't complete the deserialization
/// </param>
/// <param name="_inferredLength">
/// The Inferred Length of the array, from a "Condensed Array" already found in the XML
/// </param>
/// <returns>
/// A properly formed <see cref="CArrayDeserializationHelper"/> object.
/// </returns>
private CArrayDeserializationHelper CreateArrayDeserializationHelper(XmlElement _xml,
Type _type,
CWorkingObject _workingObject,
int _inferredLength)
{
CArrayDeserializationHelper arrayHelper;
if (_workingObject.IsSet)
{
arrayHelper = new CArrayDeserializationHelper(_workingObject.WorkingObject as Array);
}
else
{
// Make sure that the array type actually is an array and it has an ElementType
var arrType = _type;
if (!arrType.IsArray)
{
throw new XDeserializationError(
"The Type specified is not an array or it does not have an ElementTypes associated with it- " +
arrType.ToString());
}
// Get info from the XML
var sLengths = XmlExtensions.GetAttributeValue(_xml, m_context.ArrayAttributeName);
var lengths = sLengths?.Split(',').Select(s => int.Parse(s)).ToArray();
var sLowerBounds = XmlExtensions.GetAttributeValue(_xml, m_context.ArrayLowerBoundAttribute);
var lowerBounds = sLowerBounds?.Split(',').Select(s => int.Parse(s)).ToArray();
if (lengths == null)
{
if (_inferredLength > -1)
{
lengths = new int[] { _inferredLength }
}
;
else
{
lengths = new int[] { InferArrayLength(_xml) }
}; // This assumes a 1-dim array at this point.
}
arrayHelper = new CArrayDeserializationHelper(arrType.GetElementType(), lengths, lowerBounds);
}
return(arrayHelper);
}
/// <summary>
/// This routine will try to figure out how large an array is based on the nodes in the
/// XML
/// </summary>
/// <param name="_xml"></param>
/// <returns></returns>
private int InferArrayLength(XmlElement _xml)
{
// XmlNode node = _xml.SelectSingleNode( @"*/*[@idx][last()]" );
var index = 0;
foreach (XmlNode node in _xml.ChildNodes)
{
var sIndex = XmlExtensions.GetAttributeValue(node, m_context.ArrayIndexAttributeName);
if (!string.IsNullOrEmpty(sIndex))
{
index = int.Parse(sIndex);
}
index++;
}
return(index);
}
/// <summary>
/// Check to see if the object has been serialized before. If it has, then make sure
/// that the reference information for it is added.
/// </summary>
/// <remarks>This routine has the overloaded</remarks>
/// <param name="_object">The object that's being serialized</param>
/// <param name="_elementForObject">
/// The element that the object is being serialized to
/// </param>
/// <returns>TRUE if the object is a duplicate, FALSE if it is a "new" object</returns>
private bool HandleDuplicateReferences(object _object, XmlElement _elementForObject)
{
var oType = _object.GetType();
if (oType.IsPrimitive)
{
return(false);
}
if (oType == TYPEOF_STRING && !m_context.DuplicateStringsCanBeReferredTo)
{
return(false);
}
if (oType.IsEnum)
{
return(false);
}
if (m_references.TryGetValue(_object, out var refElem)) // The object was serialized already
{
if (ReferenceEquals(_elementForObject, refElem)) // If this IS the referenced element, then skip it
{
return(false);
}
var refId = XmlExtensions.GetAttributeValue(refElem, m_context.ReferenceIdAttributeName);
if (refId == null) // The object that was serialized doesn't have its RefID set yet
{
refId = m_refId.ToString();
XmlExtensions.AddAttribute(refElem, m_context.ReferenceIdAttributeName, refId);
m_refId++;
}
// Add the "ReferTo" attribute to the xml
XmlExtensions.AddAttribute(_elementForObject, m_context.ReferToAttributeName, refId);
// Remove a "Type" attribute (if it exists) because this becomes redundant with
// the presence of RefTo
XmlExtensions.RemoveAttribute(_elementForObject, m_context.TypeAttributeName);
return(true);
}
m_references.Add(_object, _elementForObject);
return(false);
}
/// <summary>
/// This "different" serializer handles Properties, not Fields, and conforms to the
/// conventions found in Microsoft's Entity Framework
/// </summary>
/// <param name="_object"></param>
/// <param name="_useType"></param>
/// <param name="_elementForObject"></param>
private void SerializeUsingEntitySemantics(object _object, Type _useType, XmlElement _elementForObject)
{
XmlExtensions.AddAttribute(_elementForObject, m_context.UseEntitySemanticsAttributeName, "1");
// Gets (cached) type data pertinent to serializing an Entity
var typeData = CEntityTypeData.GetTypeData(_useType);
// First serialize all the "single" properties- No collections
for (var i = 0; i < typeData.NonCollectionProperties.Length; i++)
{
var prop = typeData.NonCollectionProperties[i];
var val = prop.GetValue(_object);
FrameworkSerialize(prop.Name, val, _elementForObject, prop.PropertyType);
}
// Now serialize all the collections which are presumed to be the "Many" in a
// Many-To-One relationship. The exact Type of the collection in this object is
// irrelevant because the collection should merely implement ICollection for the
// deserialization, and the deserialization target class should determine the exact
// collection Type, or if its an Interface the PreferredCollectionType on the
// AUseEntitySemantics attribute will dictate what to create.
for (var i = 0; i < typeData.CollectionProperties.Length; i++)
{
var col = typeData.CollectionProperties[i];
var collectionElement = XmlExtensions.AddElement(_elementForObject, col.Name);
Type elementType = null; // set if the PropertyType is a generic collection
if (col.PropertyType.IsGenericType)
{
elementType = col.PropertyType.GetGenericArguments()[0];
}
foreach (var item in col.GetValue(_object) as System.Collections.IEnumerable)
{
FrameworkSerialize(m_context.ArrayElementName, item, collectionElement, elementType);
}
}
}
/// <summary>
/// Create an XmlElement for an object. Do not populate the new element.
/// </summary>
/// <remarks>
/// FieldRenamers are NOT called at this level- the caller of this method needs to
/// handle all field renaming
/// </remarks>
/// <param name="_elementName">
/// The name that should be assigned to the newly created element
/// </param>
/// <param name="_expectedType">
/// The expected type of the object. Used to decide whether or not to add explicit Type
/// data
/// </param>
/// <param name="_object">The object that is being serialized</param>
/// <param name="_parentNode">The XML node that the new node will be a child of</param>
/// <returns>An XmlElement with some basic attributes for an object</returns>
private XmlElement CreateElementForValue(string _elementName, object _object, XmlNode _parentNode, Type _expectedType)
{
var fixedElementName = FixMemberName(_elementName);
var elem = XmlExtensions.CreateElement(_parentNode, fixedElementName);
if (_object == null)
{
XmlExtensions.AddAttribute(elem, m_context.NullAttributeName, m_context.NullAttributeValue);
}
else
{
var oType = _object.GetType();
oType = CEntityTypeData.StripProxyType(oType);
if (_expectedType != oType) // There must be a Type attribute added
{
XmlExtensions.AddAttribute(elem, m_context.TypeAttributeName, oType.AssemblyQualifiedName);
}
}
return(elem);
}
/// <summary>
/// Use this method when an Array field needs to be added to the XML serialization
/// </summary>
/// <remarks>
/// For element types that are primitives and strings, build a comma-separated list of
/// values that should end up taking less space. For all other element types, create
/// child-elements for each array element.
/// </remarks>
/// <param name="_array">The array to add to the XML Element</param>
/// <param name="_elementToAddTo">The XML Element that is to contain the array</param>
private void AddArrayToXml(Array _array, XmlElement _elementToAddTo)
{
if (_array.Rank != 1)
{
AddMultiDimensionalArray(_array, _elementToAddTo);
return;
}
var arrayType = _array.GetType();
var elementType = arrayType.GetElementType();
var count = _array.Length;
var lowerBound = _array.GetLowerBound(0);
var upperBound = _array.GetUpperBound(0);
XmlExtensions.AddAttribute(_elementToAddTo, m_context.ArrayAttributeName, count);
if (lowerBound != 0)
{
XmlExtensions.AddAttribute(_elementToAddTo, m_context.ArrayLowerBoundAttribute, lowerBound);
}
if (elementType.IsPrimitive && !m_context.AllArraysHaveExplicitElements)
{
// Helper doesn't care what the element type is, so we screen it first by making
// sure its a primitive.
_elementToAddTo.InnerText = Lib.ConvertArrayToString(_array);
}
else if (elementType == TYPEOF_STRING && !m_context.AllArraysHaveExplicitElements)
{
// Strings could theoretically be treated with the same helper used above IF
// they never contained commas.
var str = ConvertStringArrayToCommaList(_array);
_elementToAddTo.InnerText = str;
}
else
{
var skipped = false;
var elementName = GetNameForCollectionElement();
for (var i = lowerBound; i <= upperBound; i++)
{
var arrayElementValue = _array.GetValue(i);
if (arrayElementValue == null && m_context.RemoveNullValuesFromXml)
{
skipped = true;
}
else
{
var elem = FrameworkSerialize(elementName, arrayElementValue, _elementToAddTo, elementType);
if (m_context.ArrayElementsIncludeIndicies || skipped)
{
XmlExtensions.AddAttribute(elem, m_context.ArrayIndexAttributeName, i);
}
skipped = false;
}
}
}
}
