/// <inheritdoc />
/// <remarks>The function uses Convert class functionality to convert from XmlValue of child nodes into the target type.</remarks>
public object ProcessElements(XmlElement _parent_element, Type _target_type, X2OConfig _config)
{
if (!_target_type.IsValueType && !_target_type.Equals(typeof(string)))
{
return(null);
}
var xval = _parent_element.ChildNodes[0].Value;
var tgt_type_val = Convert.ChangeType(xval, _target_type);
return(tgt_type_val);
}
/// <inheritdoc />
/// <remarks>
/// The function looks for the fromFile attribute, and if found, and there are no children it uses the X2OReader to
/// read this file and desrialize its content, which is then returned as the value of this element.
/// </remarks>
public object ProcessElements(XmlElement _parent_element, Type _target_type, X2OConfig _config)
{
var external_config_attr = _parent_element.Attributes["fromFile"];
if (external_config_attr != null && !_parent_element.HasChildNodes)
{
foreach (var possible_file in FindExistingFiles(external_config_attr.Value, _config))
{
try
{
var result = X2OReader.ReadFromFile(possible_file, _config);
if (result != null)
{
return(result);
}
}
catch { }
}
}
return(null);
}
/// <summary>
/// Based on the filename in the attribute for loading the external file, it finds the files, which exists
/// and could be loaded to be read.
/// It uses the ExternalConfigSearchPaths property of the X2OConfig, after it is not found in the application current directory.
/// </summary>
private IEnumerable <string> FindExistingFiles(string _filename, X2OConfig _config)
{
var fi = new System.IO.FileInfo(_filename);
if (fi.Exists)
{
yield return(fi.FullName);
}
if (_config?.ExternalConfigSearchPaths != null)
{
foreach (var search_path in _config.ExternalConfigSearchPaths)
{
var pathname = System.IO.Path.Combine(search_path, _filename);
fi = new System.IO.FileInfo(pathname);
if (fi.Exists)
{
yield return(fi.FullName);
}
}
}
yield break;
}
/// <summary>
/// This function tries to create the instance of the target type according to the information in _declared_type and _parent_element.
/// In this implementation, it is able to create only the List<object> or List<T> types, according to the _declared_type and
/// only in cases, that the _declared_type is convertible into these Lists.
/// </summary>
public virtual EnumerableInfo?CreateEnumerable(XmlElement _parent_element, Type _target_type, X2OConfig _config)
{
Action <IEnumerable, object> add_action = (l, i) => l.GetType().GetMethod("Add").Invoke(l, new[] { i });
// find if it is generic, find the generic type, create list of that type, and try if it can convert into declared type
if (_target_type.IsGenericType && _target_type.GenericTypeArguments.Length == 1)
{
// it is generic type, like List<T> or IEnumerable<T>
var item_type = _target_type.GenericTypeArguments[0];
var tgt_type = typeof(List <>).MakeGenericType(item_type);
if (_target_type.IsAssignableFrom(tgt_type))
{
try
{
return(new EnumerableInfo()
{
Enumerable = Activator.CreateInstance(tgt_type) as IEnumerable,
DeclaredItemType = item_type,
AddAction = add_action
});
}
catch { }
}
}
else
{
if (_target_type.IsAssignableFrom(typeof(List <object>)))
{
try
{
return(new EnumerableInfo()
{
Enumerable = new List <object>(),
DeclaredItemType = typeof(object),
AddAction = add_action
});
}
catch { }
}
}
return(null);
}
/// <inheritdoc />
/// <remarks>
/// This function firstly check, if the type will be IEnumerable.
/// Then it tries to create the instance and get information about the enumerable by calling function CreateEnumerable.
/// If successful, it goes through all the child nodes of _parent_element and deserializes the objects, which are than add
/// using the AddAction.
/// </remarks>
public virtual object ProcessElements(XmlElement _parent_element, Type _target_type, X2OConfig _config)
{
// if the declared type is not the IEnumerable, we cannot help here
if (!typeof(IEnumerable).IsAssignableFrom(_target_type))
{
return(null);
}
var enumerable_info = CreateEnumerable(_parent_element, _target_type, _config);
if (!enumerable_info.HasValue)
{
return(null);
}
foreach (XmlElement element in _parent_element.ChildNodes)
{
var item = _config.Processor.ProcessElements(element, enumerable_info.Value.DeclaredItemType, _config);
enumerable_info.Value.AddAction(enumerable_info.Value.Enumerable, item);
}
return(enumerable_info.Value.Enumerable);
}
/// <summary></summary>
public virtual DictionaryInfo?CreateDictionary(XmlElement _parent_element, Type _target_type, X2OConfig _config)
{
if (_target_type.IsGenericType && _target_type.GenericTypeArguments.Length == 2)
{
// generic dictionary like Dictionary<T1, T2>
var key_type = _target_type.GenericTypeArguments[0];
var value_type = _target_type.GenericTypeArguments[1];
var dict_type = typeof(Dictionary <,>).MakeGenericType(key_type, value_type);
if (dict_type.IsAssignableFrom(_target_type))
{
try
{
var dict = Activator.CreateInstance(_target_type) as IDictionary;
// declared type is derived from Dictionary<T1,T2> and we guessed the type parameters correctly
var dict_info = new DictionaryInfo()
{
Dictionary = dict,
KeyType = key_type,
ValueType = value_type
};
return(dict_info);
}
catch { }
}
}
// in any other cases, we cannot guess the key and value types without traversing the object hierarchy
// for these cases, it is better to return without guessing
// user can override this function to get the correct types
return(null);
}
/// <inheritdoc />
/// <remarks>
/// </remarks>
public virtual object ProcessElements(XmlElement _parent_element, Type _target_type, X2OConfig _config)
{
// if the declared type is not the IDictionary, we cannot help here
if (!typeof(IDictionary).IsAssignableFrom(_target_type))
{
return(null);
}
var dictionary_info = CreateDictionary(_parent_element, _target_type, _config);
if (!dictionary_info.HasValue)
{
return(null);
}
foreach (XmlElement element in _parent_element.ChildNodes)
{
if (element.Name == "Item")
{
XmlElement key_node = null, value_node = null;
foreach (XmlElement item_element in element.ChildNodes)
{
if (item_element.Name == "Key")
{
key_node = item_element;
}
if (item_element.Name == "Value")
{
value_node = item_element;
}
}
if (key_node != null)
{
var key = _config.Processor.ProcessElements(key_node, dictionary_info.Value.KeyType, _config);
object value = null;
if (value_node != null)
{
value = _config.Processor.ProcessElements(value_node, dictionary_info.Value.ValueType, _config);
}
if (key != null)
{
dictionary_info.Value.Dictionary.Add(key, value);
}
}
}
}
return(dictionary_info.Value.Dictionary);
}
/// <summary>
/// Based on the _declared_type and XmlElement settings of _parent_element it creates the target object, where the values from the
/// child nodes are to be read.
/// </summary>
/// <returns>The instance of the target object or null, if the processor doesn't know how to read such type of object.</returns>
public virtual object CreateInstance(XmlElement _parent_element, Type _target_type, X2OConfig _config)
{
// try the declared type
try
{
return(Activator.CreateInstance(_target_type));
}
catch { }
// or in some cases it may happen, that the node has the name of the type
{
var type = _config.Processor.GetTypeByName(_parent_element.Name, _config);
try
{
return(Activator.CreateInstance(type));
}
catch { }
}
return(null);
}
/// <inheritdoc />
public virtual object ProcessElements(XmlElement _parent_element, Type _target_type, X2OConfig _config)
{
var inst = CreateInstance(_parent_element, _target_type, _config);
if (inst == null)
{
return(null);
}
foreach (XmlElement element in _parent_element.ChildNodes)
{
var member_info = inst.GetType().GetMembers().Single(m => m.Name == element.Name);
var member_type = member_info.GetTypeOfMember();
var val = _config.Processor.ProcessElements(element, member_type, _config);
member_info.SetMemberValue(inst, val);
}
return(inst);
}
