WPF C#在不向视图模型中添加额外变量的情况下获取对象属性

Question

我目前正试图实现一个组合框绑定到一个列表和一些显示所选对象详细信息的标签。绑定到组合框没有任何问题，但我不想在ViewModel中添加额外的变量来显示我的汽车对象的名称和速度。

是否有任何方法可以将所选组合框项目的对象变量映射到标签上，而无需将其他变量添加到我的ViewModel中？

这是我目前正在使用的代码

MainWondow.xaml.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
namespace StackOF
{
/// <summary>
/// Interaction logic for MainWindow.xaml
/// </summary>
public partial class MainWindow : Window
{
private ViewModel viewModel;
public MainWindow()
{
viewModel = new ViewModel();
DataContext = viewModel;
InitializeComponent();
}
}
}

ViewModel.cs

using _02_WPFCarInfo.AutoKlassen;
using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.ComponentModel;
using System.Linq;
using System.Runtime.CompilerServices;
using System.Text;
using System.Threading.Tasks;
namespace StackOF
{
public class ViewModel : INotifyPropertyChanged
{
private ObservableCollection<AutoModel> _autoModels;
private AutoModel selectedModel;
public ObservableCollection<AutoModel> AutoModels
{
get { return _autoModels; }
set
{ 
_autoModels = value;
OnPropertyChanged();
}
}
public AutoModel SelectedModel
{
get { return selectedModel; }
set
{
selectedModel = value;
OnPropertyChanged();
}
}

public ViewModel()
{
_autoModels = generateCars();
}

private ObservableCollection<AutoModel> generateCars()
{
AutoModel model1 = new AutoModel();
AutoModel model2 = new AutoModel();
AutoModel model3 = new AutoModel();
model1.name = "Mercedes C12 Pro";
model1.speed = "125 km\h";
model2.name = "Audi A12";
model2.speed = "236 km\h";

model3.name = "Audi S20 Pro";
model3.speed = "300 km\h";

ObservableCollection<AutoModel> cars = new ObservableCollection<AutoModel>();
cars.Add(model1);
cars.Add(model2);
cars.Add(model3);
return cars;
}
public event PropertyChangedEventHandler PropertyChanged;
protected virtual void OnPropertyChanged([CallerMemberName] string propertyName = null)
{
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
}
}
}

主窗口.xaml

<Window x:Class="StackOF.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:local="clr-namespace:StackOF"
mc:Ignorable="d"
Title="MainWindow" Height="450" Width="800">
<Grid>
<ComboBox SelectedItem="{Binding SelectedModel}" DisplayMemberPath="name" ItemsSource="{Binding AutoModels}" HorizontalAlignment="Center" Margin="0,164,0,0" VerticalAlignment="Top" Width="212"/>
<Label Content="Name:" HorizontalAlignment="Left" Margin="294,231,0,0" VerticalAlignment="Top"/>
<Label Content="Speed:" HorizontalAlignment="Left" Margin="294,262,0,0" VerticalAlignment="Top"/>
<TextBlock HorizontalAlignment="Center" Margin="0,241,0,0" TextWrapping="Wrap" Text="---" VerticalAlignment="Top" RenderTransformOrigin="0.287,-1.303"/>
<TextBlock HorizontalAlignment="Center" Margin="0,267,0,0" TextWrapping="Wrap" Text="---" VerticalAlignment="Top" RenderTransformOrigin="0.287,-1.303"/>
</Grid>
</Window>

AutoModel.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace _02_WPFCarInfo.AutoKlassen
{
public class AutoModel
{
public String name { get; set; }
public String speed { get; set; }
public AutoModel()
{
this.speed = String.Empty;
this.name = String.Empty;
}
public AutoModel(String name, String speed)
{
this.speed = speed;
this.name = name;
}
}
}

我想了一些类似的东西：

<TextBlock HorizontalAlignment="Center" Margin="0,241,0,0" TextWrapping="Wrap" Text="{Binding SelectedModel.name}" VerticalAlignment="Top" RenderTransformOrigin="0.287,-1.303"/>
<TextBlock HorizontalAlignment="Center" Margin="0,267,0,0" TextWrapping="Wrap" Text="{Binding SelectedModel.speed}" VerticalAlignment="Top" RenderTransformOrigin="0.287,-1.303"/>

但显然不可能选择"0"的变量；SelectedModel"；那样。

Answer 1

好的，nvm确实有效。只有当你在之间有一个带有打开和关闭标签的文本块时，它才不起作用

这项工作：

<TextBlock HorizontalAlignment="Center" Margin="0,241,0,0" TextWrapping="Wrap" Text="{Binding SelectedModel.name}" VerticalAlignment="Top" RenderTransformOrigin="0.287,-1.303"/>

但这不是

<TextBlock HorizontalAlignment="Center" Margin="0,241,0,0" TextWrapping="Wrap" Text="{Binding SelectedModel.name}" VerticalAlignment="Top" RenderTransformOrigin="0.287,-1.303">---</TextBlock>