/// <summary>
/// Sets the value of field referred to by specified mapping, inside specified
/// instance with specified type
/// </summary>
/// <param name="desc">FieldMapping object representing the field</param>
/// <param name="fieldValue">Value to set</param>
/// <param name="contType">Type of containing object</param>
/// <param name="contInst">Containing object</param>
/// <returns></returns>
public static bool SetFieldValue(FieldMapping desc, Object fieldValue, Type contType, Object contInst)
{
bool written = false;
if (null == desc.ValueSetter) // We haven't figured this out before?
{
PropertyInfo pi = null;
MethodInfo mi = null;
//
// If the field is public, then that's what we'll use to set the value!
//
if (desc.FieldInfo.IsPublic)
{
desc.ValueSetter = desc.FieldInfo;
desc.ValueSetType = desc.FieldInfo.FieldType;
}
else
{
String pascalName = Helpers.ToPascalCase(desc.ObjBindingName);
//
// Now we look for a write-access property with a pascal case version
// of the field name (e.g. Documentation). //! What about overloads?
//
if (null != (pi = contType.GetProperty(pascalName)) && pi.CanWrite)
{
desc.ValueSetter = pi;
desc.ValueSetType = pi.PropertyType;
}
else if (null != (mi = contType.GetMethod("set" + pascalName,
new Type[] { desc.FieldInfo.FieldType })))
{
desc.ValueSetter = mi;
desc.ValueSetType = desc.FieldInfo.FieldType;
}
else
{
Console.WriteLine(String.Format("Cannot find {0} write property in {1}",
pascalName, contInst.GetType()));
}
}
}
if (null == desc.ValueSetter)
{
throw new Exception(String.Format("Unable to find a way to populate value of {0} in {1}",
desc.XmlName, null != contInst ? contInst.ToString() : "null"));
}
written = InvokeSet(desc.ValueSetter, fieldValue, desc.ValueSetType, contInst);
return(written);
}
/// <summary>
/// Processes a dictionary object, by writing all its key based elements
/// </summary>
/// <typeparam name="TA">Type of key within the dictionary</typeparam>
/// <typeparam name="TB">Type of value within the dictionary</typeparam>
/// <param name="dict">Dictionary object</param>
/// <param name="dictMapping">Field mapping describing the dictionary itself within its containing object</param>
/// <param name="writer">XmlWriter object</param>
private void ProcessDictElements <TA, TB>(IDictionary <TA, TB> dict, FieldMapping dictMapping, XmlWriter writer)
{
foreach (TA key in dict.Keys)
{
TB entry = dict[key];
writer.WriteStartElement(dictMapping.XmlName); // Entry tag
String mapKeyValue = key.ToString();
writer.WriteAttributeString(dictMapping.KeyName, mapKeyValue); // Write key attribute
Write(entry, null, writer, dictMapping.MapEntryXmlName); // Write the entry
writer.WriteEndElement(); // Close entry tag
}
}
/// <summary>
/// Writes out those fields of specified object that are mapped to XML attributes
/// </summary>
/// <param name="obj">Object to write its attributes</param>
/// <param name="em">Element mapping of the object</param>
/// <param name="writer">XmlWriter object</param>
private void WriteAttributes(Object obj, ElementMapping em, XmlWriter writer)
{
Type objType = obj.GetType();
for (int i = 0, length = null != em.Attributes ? em.Attributes.Count : 0; i < length; i++)
{
FieldMapping fm = em.Attributes[i];
Object value = Helpers.GetFieldValue(fm, objType, obj, typeof(String));
if (null != value)
{
String strValue = value.ToString();
writer.WriteAttributeString(fm.XmlName, strValue);
}
}
}
/// <summary>
/// Returns an element mapping object representing the specified type
/// </summary>
/// <param name="t">Type to return its element mapping</param>
/// <returns>Element mapping object if found, otherwise null</returns>
public ElementMapping GetElementMapping(Type t)
{
ElementMapping res = null;
String cacheKey = t.FullName;
if (!elemCache.TryGetValue(cacheKey, out res))
{
ElementMapping em = new ElementMapping();
em.XmlName = Helpers.ExtractElementName(t);
FieldInfo[] fis = t.GetFields(BindingFlags.Instance | BindingFlags.NonPublic | BindingFlags.Public);
for (int i = 0; i < fis.Length; i++)
{
FieldInfo fi = fis[i];
FieldMapping desc = GetFieldMapping(fi, fi.Name);
if (null == desc)
{
continue;
}
switch (desc.NodeType)
{
case NodeType.Attribute:
em.AddAttribute(desc);
break;
default:
em.AddSubElement(desc);
break;
}
}
elemCache.Add(cacheKey, em);
res = em;
}
return(res);
}
/// <summary>
/// Populates those field of the specified object that are mapped to XML attributes
/// </summary>
/// <param name="t">Type of object</param>
/// <param name="inst">Object to populate</param>
/// <param name="reader">XmlReader to read from</param>
private void PopulateAttributes(Type t, Object inst, XmlReader reader)
{
int i = -1;
for (i = 0; i < reader.AttributeCount; i++)
{
reader.MoveToAttribute(i);
FieldMapping desc = ots.LookupField(t, reader.Name);
if (null != desc)
{
Helpers.SetFieldValue(desc, reader.Value, t, inst);
}
}
if (i >= 0)
{
reader.MoveToElement();
}
}
/// <summary>
/// Looks up and returns a field mapping object given the containing type and the
/// XML tag/attribute name within the scope of the containing object
/// </summary>
/// <param name="t">The type of the containing object</param>
/// <param name="xmlName">The XML tag/attribute name within the scope of the
/// containing object</param>
/// <returns>FieldMapping object if found, otherwise null</returns>
public FieldMapping LookupField(Type t, String xmlName)
{
FieldMapping res = null;
String cacheKey = t.FullName + "_" + xmlName;
if (fieldMappingCache.TryGetValue(cacheKey, out res))
{
return(res);
}
if (null == res)
{
FieldInfo[] fis = null;
if (!fieldsCache.TryGetValue(t.FullName, out fis))
{
fis = t.GetFields(BindingFlags.Instance | BindingFlags.NonPublic | BindingFlags.Public);
fieldsCache.Add(t.FullName, fis);
}
for (int i = 0; i < fis.Length; i++)
{
FieldInfo fi = fis[i];
FieldMapping desc = GetFieldMapping(fi, xmlName);
if (null == desc)
{
continue;
}
if (String.Equals(xmlName, desc.XmlName))
{
res = desc;
break;
}
}
}
return(res);
}
/// <summary>
/// Writes out the specified object. This method writes the element for the object, and
/// recursively writes out all attributes and sub elements.
/// </summary>
/// <param name="obj">Object to write</param>
/// <param name="fm">Field mapping of the object within its containing object (optional).
/// When provided, the logic will use it to determine whether element is to be "inline"'d,
/// in which case the logic will not write an outer tag for it. Also the XmlName field of the
/// mapping will take precedence in determining the tag name over the name mentioned in
/// the element mapping.
/// </param>
/// <param name="writer">XmlWriter object</param>
/// <param name="tagName">Specifies the tag name to use for the object (optional). This
/// parameter can be used to override what the tag name that the logic would normally use,
/// it is mainly to be used when writing collections, since the name of each entry's tag
/// can be customized at the collection declaration level (e.g. via [ElementMap] or
/// [ElemenList] attributes). When this parameter is set to null, the logic will get the
/// name from either the field mapping object (if provided) or from the element mapping object.
/// </param>
private void Write(Object obj, FieldMapping fm, XmlWriter writer, String tagName)
{
Type objType = obj.GetType();
ElementMapping em = ots.GetElementMapping(objType);
if (null == em)
{
throw new ArgumentException("Don;t know how to handle this object", objType.ToString());
}
String xmlName = tagName; // Allow caller to override tag name
//
// If the tag name was not overriden by the caller, then it would be the name
// specified by the mapping in the elment's container, if not specified then
// it is the name as specified by the element mapping.
//
if (null == xmlName) // Tag name not provided, use the one in field mapping
{
xmlName = null != fm ? fm.XmlName : em.XmlName;
}
//
// For nodes that are marked as inline, we don't write a tag for them.
//
bool inline = null != fm ? fm.Inline : false;
if (!inline)
{
writer.WriteStartElement(xmlName); // Start of element
WriteAttributes(obj, em, writer); // Write attributes
}
int i = 0, length = length = null != em.SubElements ? em.SubElements.Count : 0;
//
// If the element has no sub-elements, we treat it as a leaf node so we write its
// body value. Note that we do the XML encoding ourselves because XmlWriter
// implementation does not encode single or double quotes within the body of a tag,
// but SimpleXml framework does.
//
if (0 == length)
{
writer.WriteRaw(Helpers.XmlEncode(obj.ToString()));
}
else // Otherwise, drill down the object
{
//
// Write sub elements.
//
for (i = 0; i < length; i++)
{
FieldMapping subMapping = em.SubElements[i];
Object value = null;
switch (subMapping.NodeType)
{
case NodeType.Element:
value = Helpers.GetFieldValue(subMapping, objType, obj, subMapping.ValueType);
if (null != value)
{
Write(value, subMapping, writer, null); // Drill down
}
break;
case NodeType.Map:
{
//
// Note that we assume that map based fields are using an IDictionary
// based object, with its key being of type String.
//
value = Helpers.GetFieldValue(subMapping, objType, obj, subMapping.ValueType);
if (null != value)
{
Type gt = typeof(IDictionary <,>);
if (null != value.GetType().GetInterface("IDictionary`2"))
{
MethodInfo mi = this.GetType().GetMethod("ProcessDictElements",
BindingFlags.NonPublic | BindingFlags.Instance);
MethodInfo si = mi.MakeGenericMethod(value.GetType().GetGenericArguments());
si.Invoke(this, new Object[] { value, subMapping, writer });
}
}
break;
}
case NodeType.List:
{
//
// Note that we assume that list based fields are using an IList based object.
//
value = Helpers.GetFieldValue(subMapping, objType, obj, subMapping.ValueType);
if (null != value)
{
Type gt = typeof(IList <>);
if (null != value.GetType().GetInterface("IList`1"))
{
MethodInfo mi = this.GetType().GetMethod("ProcessListElements",
BindingFlags.NonPublic | BindingFlags.Instance);
MethodInfo si = mi.MakeGenericMethod(value.GetType().GetGenericArguments());
si.Invoke(this, new Object[] { value, subMapping, writer });
}
}
break;
}
}
}
}
if (!inline)
{
writer.WriteEndElement(); // End of element
}
}
/// <summary>
/// Returns the value of field referred to be specified mapping, inside specified
/// instance with specified type
/// </summary>
/// <param name="desc">FieldMapping object representing the field</param>
/// <param name="contType">Type of containing object</param>
/// <param name="contInst">Contianing object</param>
/// <param name="valueAsType"></param>
/// <returns></returns>
public static Object GetFieldValue(FieldMapping desc, Type contType, Object contInst, Type valueAsType)
{
Object res = null;
if (null == desc.ValueGetter) // We haven't figured this out before?
{
PropertyInfo pi = null;
MethodInfo mi = null;
//
// If the field is public, then that's what we'll use to get the value!
//
if (desc.FieldInfo.IsPublic)
{
desc.ValueGetter = desc.FieldInfo;
desc.ValueGetType = desc.FieldInfo.FieldType;
}
else
{
String pascalName = Helpers.ToPascalCase(desc.ObjBindingName);
//
// Now we look for a read-access property with a pascal case version
// of the field name (e.g. Documentation). //! What about overloads?
//
if (null != (pi = contType.GetProperty(pascalName)) && pi.CanRead)
{
desc.ValueGetter = pi;
desc.ValueGetType = pi.PropertyType;
}
else if (null != (mi = contType.GetMethod("get" + pascalName)))
{
desc.ValueGetter = mi;
desc.ValueGetType = desc.FieldInfo.FieldType;
}
else
{
Console.WriteLine(String.Format("Cannot find {0} read property in {1}",
pascalName, contInst.GetType()));
}
}
}
if (null == desc.ValueGetter)
{
throw new Exception(String.Format("Unable to find a way to read value of {0} in {1}",
desc.ObjBindingName, null != contInst ? contInst.ToString() : "null"));
}
res = InvokeGet(desc.ValueGetter, desc.ValueType, valueAsType, contInst);
if (null != res && !IsTypeDescendantOf(res, valueAsType))
{
if (res is Boolean)
{
res = ((Boolean)res) ? "true" : "false";
}
else
{
res = ChangeType(res, valueAsType);
}
}
return(res);
}
/// <summary>
/// Reads and returns an object of specified type from specified XmlReader. This
/// method instantiates an object of specified type, and recursively populates
/// its fields from attributes and sub elements.
/// </summary>
/// <param name="t">Type of object</param>
/// <param name="r">XmlReader object</param>
/// <returns>The read object</returns>
public Object Read(Type t, XmlReader r)
{
using (XmlReader reader = r.ReadSubtree())
{
reader.Read();
//
// We assume reader is positioned on the XML element for the specified type
//
Object res = InstantiateObject(t);
PopulateAttributes(t, res, reader); // Populate from attributes if any
//
// This variable is used in the situations when we read the content
// of a node, in which case the pointer has already been advanced to
// the next node so there's no need to call Read().
//
bool dontAdvance = false;
while (dontAdvance || reader.Read())
{
dontAdvance = false; // Clear the flag
if (reader.NodeType == XmlNodeType.EndElement || reader.NodeType == XmlNodeType.Text)
{
continue;
}
FieldMapping desc = ots.LookupField(t, reader.Name);
if (null == desc)
{
//Console.WriteLine(string.Format("{0} skipped. within type: {1}", reader.Name, t.ToString()));
reader.Skip();
continue; // Skip ones we don't care for
}
Object fieldValue = null;
switch (desc.NodeType)
{
case NodeType.Element:
if (Helpers.IsSerializable(desc.FieldInfo.FieldType))
{
fieldValue = Read(desc.FieldInfo.FieldType, reader);
}
else
{
fieldValue = reader.ReadElementContentAsString();
dontAdvance = true;
}
Helpers.SetFieldValue(desc, fieldValue, t, res);
break;
case NodeType.Map:
//
// Ensure we have a dictionary instance.
//
Object dict = desc.FieldInfo.GetValue(res);
if (null == dict)
{
Type t1 = typeof(Dictionary <,>);
Type[] args = { desc.MapEntryKeyType, desc.MapEntryValueType };
Type t2 = t1.MakeGenericType(args);
dict = Activator.CreateInstance(t2);
Helpers.SetFieldValue(desc.ObjBindingName, dict, t, res);
}
String key = reader.GetAttribute(desc.KeyName); // Get the key
//
// Get the entry value
//
fieldValue = null;
if (reader.ReadToDescendant(desc.MapEntryXmlName))
{
if (Helpers.IsSerializable(desc.MapEntryValueType))
{
fieldValue = Read(desc.MapEntryValueType, reader);
}
else
{
fieldValue = reader.ReadElementContentAsString();
dontAdvance = true;
}
if (null != fieldValue)
{
MethodInfo mi = desc.ValueType.GetMethod("Add");
mi.Invoke(dict, new Object[] { key, fieldValue });
}
}
break;
case NodeType.List:
//
// Ensure we have a dictionary instance.
//
Object list = desc.FieldInfo.GetValue(res);
if (null == list)
{
Type t1 = typeof(List <>);
Type[] args = { desc.MapEntryValueType };
Type t2 = t1.MakeGenericType(args);
list = Activator.CreateInstance(t2);
Helpers.SetFieldValue(desc.ObjBindingName, list, t, res);
}
//
// Get the entry value
//
fieldValue = null;
if (Helpers.IsSerializable(desc.MapEntryValueType))
{
fieldValue = Read(desc.MapEntryValueType, reader);
}
else
{
fieldValue = reader.ReadElementContentAsString();
dontAdvance = true;
}
if (null != fieldValue)
{
MethodInfo mi = list.GetType().GetMethod("Add");
mi.Invoke(list, new Object[] { fieldValue });
}
break;
}
}
return(res);
}
}
/// <summary>
/// Returns a field mapping object given a FieldInfo object
/// </summary>
/// <param name="fi">FieldInfo object representing a field within its container</param>
/// <param name="cacheKeyValue">Key to be used by field mapping caching</param>
/// <returns>FieldMapping object if found, otherwise null</returns>
public FieldMapping GetFieldMapping(FieldInfo fi, String cacheKeyValue)
{
FieldMapping desc = null;
BaseAttribute attr = Helpers.ExtractAttribute(fi);
if (null != attr)
{
String cacheKey = fi.DeclaringType.FullName + "_" + cacheKeyValue;
if (!fieldMappingCache.TryGetValue(cacheKey, out desc))
{
if (attr is XmlAttributeAttribute)
{
XmlAttributeAttribute attrAttr = attr as XmlAttributeAttribute;
desc = new FieldMapping(NodeType.Attribute);
desc.XmlName = null != attrAttr.Name ? attrAttr.Name : fi.Name;
desc.Required = attrAttr.Required;
desc.ValueType = fi.FieldType;
desc.ObjBindingName = fi.Name;
desc.FieldInfo = fi;
}
else if (attr is ElementAttribute)
{
ElementAttribute elemAttr = attr as ElementAttribute;
desc = new FieldMapping(NodeType.Element);
desc.XmlName = null != elemAttr.Name ? elemAttr.Name : fi.Name;
desc.Required = elemAttr.Required;
desc.ValueType = fi.FieldType;
desc.ObjBindingName = fi.Name;
desc.FieldInfo = fi;
}
else if (attr is ElementMapAttribute)
{
ElementMapAttribute mapAttr = attr as ElementMapAttribute;
desc = new FieldMapping(NodeType.Map);
desc.Inline = mapAttr.Inline;
desc.KeyName = mapAttr.Key;
desc.ValueType = fi.FieldType;
desc.ObjBindingName = fi.Name;
desc.FieldInfo = fi;
//
// Get entry element name.
//
if (fi.FieldType.IsGenericType)
{
Type[] gargs = fi.FieldType.GetGenericArguments();
desc.MapEntryKeyType = gargs[0];
desc.MapEntryValueType = gargs[1];
desc.MapEntryXmlName = Helpers.ExtractElementName(desc.MapEntryValueType);
}
//
// Get map element name
//
if (mapAttr.Inline)
{
desc.XmlName = null != mapAttr.Entry ? mapAttr.Entry : "entry";
}
else
{
desc.XmlName = mapAttr.Name;
}
}
else if (attr is ElementListAttribute)
{
ElementListAttribute listAttr = attr as ElementListAttribute;
desc = new FieldMapping(NodeType.List);
desc.Inline = listAttr.Inline;
desc.ValueType = fi.FieldType;
desc.ObjBindingName = fi.Name;
desc.FieldInfo = fi;
//
// Get entry element name.
//
if (fi.FieldType.IsGenericType)
{
Type[] gargs = fi.FieldType.GetGenericArguments();
desc.MapEntryValueType = gargs[0];
//!desc.MapEntryName = Helpers.ExtractElementName(desc.MapEntryValueType);
}
//
// Get list entry name.
//
if (listAttr.Inline)
{
String entryName = null != desc.MapEntryValueType ?
Helpers.ToCamelCase(desc.MapEntryValueType.Name) : null;
desc.XmlName = null != listAttr.Entry ? listAttr.Entry :
(null != entryName ? entryName : "entry");
}
else
{
desc.XmlName = listAttr.Name;
}
}
if (desc.XmlName.Equals(cacheKeyValue))
{
fieldMappingCache.Add(cacheKey, desc);
}
}
}
return(desc);
}
