LYT-WPF-MVVM框架中的INotifyPropertyChanged

参考文档：WPF MVVM框架中的INotifyPropertyChanged - 知乎 (zhihu.com)

INotifyPropertyChanged 接口用于通知视图或 ViewModel 绑定哪个属性无关紧要；它已更新。

让我们举个例子来理解这个接口。以一个 WPF 窗口为例，其中共有三个字段：名字、姓氏和全名。在这里，名字和姓氏文本框是可编辑的。因此，根据名字和姓氏的变化，我们必须自动更新全名。

使窗户设计图

 WPF 窗口的 XAML 代码如下

<Window x:Class="MVVM_INotifyPropertyChanged.MainWindow" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" Title="MainWindow">  
    <Grid Width="400" Height="Auto" HorizontalAlignment="Center" VerticalAlignment="Stretch" Margin="20">  
        <Grid.RowDefinitions>  
            <RowDefinition Height="40" />  
            <RowDefinition Height="40" />  
            <RowDefinition Height="40" /> </Grid.RowDefinitions>  
        <Grid.ColumnDefinitions>  
            <ColumnDefinition Width="90" />  
            <ColumnDefinition/> </Grid.ColumnDefinitions>  
        <Label Grid.Row="0" Grid.Column="0" Content="First Name : "></Label>  
        <Label Grid.Row="1" Grid.Column="0" Content="Last Name : "></Label>  
        <Label Grid.Row="2" Grid.Column="0" Content="Full Name : "></Label>  
        <TextBox Grid.Row="0" Grid.Column="1"></TextBox>  
        <TextBox Grid.Row="1" Grid.Column="1"></TextBox>  
        <TextBox Grid.Row="2" Grid.Column="1"></TextBox>  
    </Grid>  
</Window>  

现在，我们创建一个模型，它包含一个类调用人，它有3个属性“FirstName”，“LastName”,“FullName”。

public class Person {  
    private string _fisrtname;  
    public string FirstName {  
        get {  
            return _fisrtname;  
        }  
        set {  
            _fisrtname = value;  
        }  
    }  
    private string _lastname;  
    public string LastName {  
        get {  
            return _lastname;  
        }  
        set {  
            _lastname = value;  
        }  
    }  
    private string _fullname;  
    public string FullName {  
        get {  
            return _fisrtname +" "+_lastname; ;  
        }  
        set {  
            _fullname = value;  
        }  
    }  
    public Person() {  
        _fisrtname = "Nirav";  
        _lastname = "Daraniya";  
    }  
}