public static PropertyPath <TValue> Create <TValue>(Expression <Func <TValue> > propertyExpression)
{
var path = PropertyPathVisitor.GetPath(propertyExpression);
var propertyInfos = path.Cast <PropertyInfo>().ToArray();
var parts = new PathProperty[propertyInfos.Length];
PathProperty previous = null;
for (int i = 0; i < propertyInfos.Length; i++)
{
var propertyInfo = propertyInfos[i];
var item = new PathProperty(previous, propertyInfo);
parts[i] = item;
previous = item;
}
var constants = ConstantVisitor.GetConstants(propertyExpression);
if (!constants.Any())
{
throw new ArgumentException("Expression contains no constants", nameof(propertyExpression));
}
//valuePath.Source = source;
var source = constants.Last().Value;
var propertyPath = new PropertyPath(parts);
return(new PropertyPath <TValue>(propertyPath, source));
}
public NotifyingPathItem(INotifyingPathItem previous, PathProperty pathProperty)
{
Ensure.NotNull(pathProperty, nameof(pathProperty));
if (previous?.PathProperty != null)
{
var type = previous.PathProperty.PropertyInfo.PropertyType;
if (type.IsValueType)
{
var message = string.Format(
"Property path cannot have structs in it. Copy by value will make subscribing error prone." + Environment.NewLine +
"The type {0} is a value type not so {1}.{2} will not notify when it changes.",
type.PrettyName(),
previous.PathProperty.PropertyInfo,
pathProperty.PropertyInfo.Name);
throw new ArgumentException(message, nameof(pathProperty));
}
if (!typeof(INotifyPropertyChanged).IsAssignableFrom(type))
{
var message = string.Format(
"All levels in the path must implement INotifyPropertyChanged." + Environment.NewLine +
"The type {0} does not so {1}.{2} will not notify when it changes.",
type.PrettyName(),
previous.PathProperty.PropertyInfo,
pathProperty.PropertyInfo.Name);
throw new ArgumentException(message, nameof(pathProperty));
}
}
this.PathProperty = pathProperty;
this.onNext = x => this.OnPropertyChanged(x.Sender, x.EventArgs);
this.onError = this.OnError;
this.PropertyChangedEventArgs = new PropertyChangedEventArgs(this.PathProperty.PropertyInfo.Name);
this.Previous = previous;
var notifyingPathItem = previous as NotifyingPathItem;
if (notifyingPathItem != null)
{
notifyingPathItem.Next = this;
}
if (previous != null)
{
this.Source = (INotifyPropertyChanged)previous.Value;
}
}
public static PropertyPath <TSource, TValue> Create <TSource, TValue>(Expression <Func <TSource, TValue> > propertyExpression)
{
var path = PropertyPathVisitor.GetPath(propertyExpression);
var propertyInfos = path.Cast <PropertyInfo>().ToArray();
var parts = new PathProperty[propertyInfos.Length];
PathProperty previous = null;
for (int i = 0; i < propertyInfos.Length; i++)
{
var propertyInfo = propertyInfos[i];
var item = new PathProperty(previous, propertyInfo);
parts[i] = item;
previous = item;
}
return(new PropertyPath <TSource, TValue>(new PropertyPath(parts)));
}
/// <summary>
/// Initializes a new instance of the <see cref="PathProperty"/> class.
/// </summary>
/// <param name="previous"></param>
/// <param name="propertyInfo">
/// The property info.
/// </param>
public PathProperty(PathProperty previous, PropertyInfo propertyInfo)
{
if (propertyInfo == null)
{
throw new ArgumentNullException(nameof(propertyInfo));
}
if (!propertyInfo.CanRead)
{
throw new ArgumentException("Propert must be readable");
}
this.Previous = previous;
if (previous != null)
{
previous.Next = this;
}
this.PropertyInfo = propertyInfo;
}
