我有一个简单的应用程序，应该添加SelectedItem从组合框到列表框。我有Model：Player

public class Player
{
    public int ID { get; set; }
    public string Name { get; set; }

    private bool _isSelected = false;
    public bool IsSelected
    {
        get { return _isSelected; }
        set { _isSelected = value; }
    }
}

和我的ViewModel中的ObservableCollection属性（玩家）

public class ViewModel
{
    public ObservableCollection<Player> Players { get; set; }
    public ObservableCollection<Player> PlayersInTournament { get; set; } = new ObservableCollection<Player>();
    public ICommand AddPlayerCommand { get; set; }
    public ViewModel()
    {            
        DataAccess access = new DataAccess();
        Players = new ObservableCollection<Player>(access.GetPlayers());//GetPlayers from DataBase
        AddPlayerCommand = new RelayCommand(AddPlayer, CanAddPlayer);
    }

    private void AddPlayer()
    {
        //Something like PlayersInTournamen.Add(SelectedPlayer);
    }

    private bool CanAddPlayer()
    {
        bool canAdd = false;
        foreach(Player player in Players)
        {
            if (player.IsSelected == true)
                canAdd = true;
        }

        return canAdd;
    }
}

属性ComboBox的（ItemSource）绑定到Players集合。当应用程序是Loaded时，ComboBox将填充数据库中的对象，当我选择其中一个对象时，它将显示在ReadOnlyTextBox中。我通过将Text属性绑定到ComboBox的ItemSelected.Name属性来实现这一点。在应用程序中有一个添加按钮，将选定的球员添加到锦标赛（ListBox）（该应用程序是关于锦标赛的）。ListBox的ItemSource是PlayersInTournament集合（见ViewModel中）。
XAML（在InitializeComponents（）之后将窗口的DataContext设置为ViewModel示例）：

<Window x:Class="ComboBoxDemoSQL.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:b="http://schemas.microsoft.com/xaml/behaviors"        
    xmlns:local="clr-namespace:ComboBoxDemoSQL"
    mc:Ignorable="d"
    Title="MainWindow" Height="450" Width="800">

<Grid>
    <Grid.ColumnDefinitions>
        <ColumnDefinition/>
        <ColumnDefinition/>
    </Grid.ColumnDefinitions>

    <Grid.RowDefinitions>
        <RowDefinition/>   
        <RowDefinition/>   
    </Grid.RowDefinitions>
    <StackPanel>
        <StackPanel  HorizontalAlignment="Center"
                     Orientation="Horizontal" Margin="0 40 0 10">

            <TextBox x:Name="HoldPlayerTextBox"
                     Width="100"
                     Text="{Binding ElementName=PlayersComboBox, Path=SelectedItem.Name}"
                     IsReadOnly="True">
            </TextBox>

            <ComboBox Name="PlayersComboBox" 
                      VerticalAlignment="Top" 
                      Margin="10 0 0 0"
                      HorizontalAlignment="Center" Width="100"
                      ItemsSource="{Binding Players}"
                      DisplayMemberPath="Name"
                      Text="Select player"
                      IsEditable="True"
                      IsReadOnly="True"/>
        </StackPanel>

        <Button Content="Add" Margin="120 0 120 0"
                Command="{Binding AddPlayerCommand}"/>

        <ListBox Margin="10" ItemsSource="{Binding PlayersInTournament}">
            <ListBox.ItemTemplate>
                <DataTemplate>
                    <StackPanel Orientation="Horizontal">
                        <TextBlock Text="{Binding Name}"/>
                        <TextBlock Text="{Binding ID}"/>
                    </StackPanel>
                </DataTemplate>
            </ListBox.ItemTemplate>
        </ListBox>
    </StackPanel>
</Grid>

照片更好理解：

所以基本上有两个问题：
1.我不知道如何将在ComboBox中选定的玩家添加到PlayersInTournament集合，因为我无法从TexBox获取该玩家的名称（因为其'Text属性绑定到另一个属性）
1.我不知道如何禁用Add Button（CanAddPlayer方法），当没有选择播放器时，我尝试添加IsSelected（见播放器模型）属性，但为了使它工作，我必须绑定到视图中的任何属性，这将改变它，但我不知道哪个属性可以用于这件事。
ICommand实现：

public class RelayCommand : ICommand
{
    public event EventHandler CanExecuteChanged
    {
        add { CommandManager.RequerySuggested += value; }
        remove { CommandManager.RequerySuggested -= value; }
    }
    private Action methodToExecute;
    private Func<bool> canExecuteEvaluator;
    public RelayCommand(Action methodToExecute, Func<bool> canExecuteEvaluator)
    {
        this.methodToExecute = methodToExecute;
        this.canExecuteEvaluator = canExecuteEvaluator;
    }
    public RelayCommand(Action methodToExecute)
        : this(methodToExecute, null)
    {
    }
    public bool CanExecute(object parameter)
    {
        if (this.canExecuteEvaluator == null)
        {
            return true;
        }
        else
        {
            bool result = this.canExecuteEvaluator.Invoke();
            return result;
        }
    }
    public void Execute(object parameter)
    {
        this.methodToExecute.Invoke();
    }
}