双向绑定 TwoWay MVVM

1前台代码

  <Grid>
        <StackPanel >
            <Grid x:Name="gridOne">
                <Grid.Resources>
                    <Style   TargetType="TextBlock">
                        <Setter Property="FontSize" Value="34"/>
                    </Style>
                </Grid.Resources>
                <Grid.ColumnDefinitions>
                    <ColumnDefinition Width="auto"/>
                    <ColumnDefinition />
                </Grid.ColumnDefinitions>
                <Grid.RowDefinitions>
                    <RowDefinition Height="auto"/>
                    <RowDefinition Height="auto"/>
                </Grid.RowDefinitions>
                <TextBlock Text="姓名：" />
                <TextBlock   Grid.Column="1" Text="{Binding Name}"/>
                <TextBlock Grid.Row="1" Text="城市：" />
                <TextBlock   Grid.Column="1" Grid.Row="1" Text="{Binding City}"/>
            </Grid>
            <Grid x:Name="gridTwp">
                <Grid.Resources>
                    <Style   TargetType="TextBlock">
                        <Setter Property="FontSize" Value="34"/>
                    </Style>
                </Grid.Resources>
                <Grid.ColumnDefinitions>
                    <ColumnDefinition Width="auto"/>
                    <ColumnDefinition />
                </Grid.ColumnDefinitions>
                <Grid.RowDefinitions>
                    <RowDefinition Height="auto"/>
                    <RowDefinition Height="auto"/>
                </Grid.RowDefinitions>
                <TextBlock Text="姓名1：" />
                <TextBox  Name="txtName"  Grid.Column="1" Text="{Binding Name,Mode=TwoWay}"/>
                <TextBlock Grid.Row="1" Text="城市1：" />
                <TextBox Name="txtCity"   InputScope="ChineseFullWidth"  Grid.Column="1" Grid.Row="1" Text="{Binding City,Mode=TwoWay}"/>
            </Grid>
        </StackPanel>
    </Grid>

2后台方法

  public class Person : INotifyPropertyChanged
        {
            public event PropertyChangedEventHandler PropertyChanged;
            protected void OnPropertyChanged([CallerMemberName] string property="")
            {
                if (PropertyChanged!=null)
                {
                    PropertyChanged(this, new  PropertyChangedEventArgs(property));
                }
            }
            private string _name;

            public string Name
            {
                get
                {
                    return _name;
                }

                set
                {
                    if (_name!=value)
                    {
                        _name = value;
                        OnPropertyChanged();
                    }
                }
            }
            private string _city;

            public string City
            {
                get
                {
                    return _city;
                }

                set
                {
                    if (_city != value)
                    {
                        _city = value;
                        OnPropertyChanged();
                    }
                }
            }

        }

3数据绑定

    Person ps = new Person { Name="小刘" ,City="北京" };
            gridOne.DataContext = ps;
            gridTwp.DataContext = ps;