// Note that this returns XamlMember which might not actually appear in XamlObjectReader. For example, XamlLanguage.Items won't be returned when there is no item in the collection.
public static IEnumerable <XamlMember> GetAllObjectReaderMembersByType(this XamlType type, IValueSerializerContext vsctx)
{
if (type.HasPositionalParameters(vsctx))
{
yield return(XamlLanguage.PositionalParameters);
yield break;
}
// Note that if the XamlType has the default constructor, we don't need "Arguments".
IEnumerable <XamlMember> args = type.ConstructionRequiresArguments ? type.GetSortedConstructorArguments() : null;
if (args != null && args.Any())
{
yield return(XamlLanguage.Arguments);
}
if (type.IsContentValue(vsctx))
{
yield return(XamlLanguage.Initialization);
yield break;
}
if (type.IsDictionary)
{
yield return(XamlLanguage.Items);
yield break;
}
foreach (var m in type.GetAllMembers())
{
// do not read constructor arguments twice (they are written inside Arguments).
if (args != null && args.Contains(m))
{
continue;
}
// do not return non-public members (of non-collection/xdata). Not sure why .NET filters out them though.
if (!m.IsReadPublic)
{
continue;
}
if (!m.IsWritePublic &&
!m.Type.IsXData &&
!m.Type.IsArray &&
!m.Type.IsCollection &&
!m.Type.IsDictionary)
{
continue;
}
yield return(m);
}
if (type.IsCollection)
{
yield return(XamlLanguage.Items);
}
}
// It expects that it is not invoked when there is no value to
// assign.
// When it is passed null, then it returns a default instance.
// For example, passing null as Int32 results in 0.
// But do not immediately try to instantiate with the type, since the type might be abstract.
object GetCorrectlyTypedValue(XamlMember xm, XamlType xt, object value, bool fallbackToString = false)
{
try
{
if (value == null)
{
if (xt.IsContentValue(service_provider)) // it is for collection/dictionary key and item
{
return(null);
}
else
{
return(xt.IsNullable ? null : xt.Invoker.CreateInstance(new object[0]));
}
}
if (ReferenceEquals(xt, null))
{
return(value);
}
// Not sure if this is really required though...
var vt = sctx.GetXamlType(value.GetType());
if (vt.CanAssignTo(xt))
{
return(value);
}
// FIXME: this could be generalized by some means, but I cannot find any.
if (xt.UnderlyingType == typeof(XamlType) && value is string)
{
value = ResolveTypeFromName((string)value);
}
// FIXME: this could be generalized by some means, but I cannot find any.
if (xt.UnderlyingType == typeof(Type))
{
value = new TypeExtension((string)value).ProvideValue(service_provider);
}
if (ReferenceEquals(xt, XamlLanguage.Type) && value is string)
{
value = new TypeExtension((string)value);
}
if (IsAllowedType(xt, value))
{
return(value);
}
var xtc = xm?.TypeConverter ?? xt.TypeConverter;
if (xtc != null && value != null)
{
var tc = xtc.ConverterInstance;
if (tc != null && tc.CanConvertFrom(service_provider, value.GetType()))
{
value = tc.ConvertFrom(service_provider, CultureInfo.InvariantCulture, value);
}
return(value);
}
}
catch (Exception ex)
{
// For + ex.Message, the runtime should print InnerException message like .NET does.
throw WithLineInfo(new XamlObjectWriterException(
String.Format("Could not convert object \'{0}' (of type {1}) to {2}: ", value, value != null ? (object)value.GetType() : "(null)", xt) + ex.Message,
ex));
}
return(fallbackToString ?
value :
throw WithLineInfo(new XamlObjectWriterException(
String.Format("Value '{0}' (of type {1}) is not of or convertible to type {2} (member {3})", value, value != null ? (object)value.GetType() : "(null)", xt, xm),
null)));
}
