c# - 未实现 INPC 的对象如何通知更改？

Question

给知道答案的人的简单问题:

我有一个基本的 Person 类，定义如下:

public class Person
{
   public Person(string name, string surname)
   {
        this.Name = name;
        this.Surname = surname;
   }

   public string Name { get; set; }

   public string Surname { get; set; }
}

一个非常简单的 View 模型

public partial class SimpleViewModel : Screen
{
    public SimpleViewModel()
    {
        this.Persons = new ObservableCollection<Person>(this.GetPersons());
    }

    private ObservableCollection<Person> persons;
    public ObservableCollection<Person> Persons
    {
        get { return this.persons; }
        set
        {
            if (this.persons == value) return;

            this.persons = value;
            this.NotifyOfPropertyChange(() => this.Persons);
        }
    }


    private Person selectedPerson;
    public Person SelectedPerson
    {
        get { return this.selectedPerson; }
        set
        {
            if (this.selectedPerson == value) return;

            this.selectedPerson = value;
            this.NotifyOfPropertyChange(() => this.SelectedPerson);
        }
    }

    IEnumerable<Person> GetPersons()
    {
        return
            new Person[]
            {
                new Person("Casey", "Stoner"),
                new Person("Giacomo", "Agostini"),
                new Person("Troy", "Bayliss"),
                new Person("Valentino", "Rossi"),
                new Person("Mick", "Doohan"),
                new Person("Kevin", "Schwantz")
            };
    }
}

和一个非常简单的 View

<Window x:Class="Test.SimpleView"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="SimpleView"
        Width="300"
        Height="300">
    <Grid>
        <Grid.RowDefinitions>
            <RowDefinition />
            <RowDefinition Height="8"/>
            <RowDefinition Height="Auto"/>
        </Grid.RowDefinitions>
        <Grid.ColumnDefinitions>
            <ColumnDefinition/>
        </Grid.ColumnDefinitions>

        <ListView x:Name="lsv"
                  ItemsSource="{Binding Persons}"
                  SelectedItem="{Binding SelectedPerson}" Grid.RowSpan="3">
            <ListView.View>
                <GridView>
                    <GridViewColumn DisplayMemberBinding="{Binding FirstName}" />
                    <GridViewColumn DisplayMemberBinding="{Binding LastName}" />
                </GridView>
            </ListView.View>
        </ListView>

        <StackPanel Grid.Row="2"
                    Grid.Column="1"
                    VerticalAlignment="Center">
            <TextBox Text="{Binding SelectedPerson.FirstName, UpdateSourceTrigger=PropertyChanged}" />
            <TextBox Text="{Binding SelectedPerson.LastName, UpdateSourceTrigger=PropertyChanged}" />
        </StackPanel>

    </Grid>
</Window>

如果我在文本框中编辑 FirstName 或 LastName， ListView 会更新。

如果 Person 没有实现 INotifyPropertyChanged，这怎么可能？

谢谢

附言ViewModel 继承Screen来自 Caliburn.Micro

Answer 1

这是使用 PropertyDescriptor 传播更改通知 as described here .

我不会依赖这种绑定(bind)。

• 它比实现 INPC 更慢且重量更重(最好对 POCO 对象的实践建议)。
• 它只适用于变化通过绑定(bind)语法启动。如果您要以编程方式更改 Name 的值，列表将不会响应。