如何最好地处理WPF单选按钮？

Question

我在XAML中有一些RadioButtons...

<StackPanel>
    <RadioButton Name="RadioButton1" GroupName="Buttons" Click="ButtonsChecked" IsChecked="True">One</RadioButton>
    <RadioButton Name="RadioButton2" GroupName="Buttons" Click="ButtonsChecked">Two</RadioButton>
    <RadioButton Name="RadioButton3" GroupName="Buttons" Click="ButtonsChecked">Three</RadioButton>
</StackPanel>

我可以在 Visual Basic 代码中处理它们的单击事件。这有效...

    Private Sub ButtonsChecked(ByVal sender As System.Object, _
                               ByVal e As System.Windows.RoutedEventArgs)
        Select Case CType(sender, RadioButton).Name
            Case "RadioButton1"
                '做某事一
                Exit Select
            Case "RadioButton2"
                '做某事二
                Exit Select
            Case "RadioButton3"
                '做某事三
                Exit Select
        End Select
    End Sub

但是，我想改进它。这段代码失败了...

<StackPanel>
    <RadioButton Name="RadioButton1" GroupName="Buttons" Click="ButtonsChecked" Command="one" IsChecked="True">One</RadioButton>
    <RadioButton Name="RadioButton2" GroupName="Buttons" Click="ButtonsChecked" Command="two">Two</RadioButton>
    <RadioButton Name="RadioButton3" GroupName="Buttons" Click="ButtonsChecked" Command="three">Three</RadioButton>
</StackPanel>

Private Sub ButtonsChecked(ByVal sender As System.Object, _
                           ByVal e As System.Windows.RoutedEventArgs)
    Select Case CType(sender, RadioButton).CommandParameter.ToString()
        Case "one"
            'Do something one
            Exit Select
        Case "two"
            'Do something two
            Exit Select
        Case "three"
            'Do something three
            Exit Select
    End Select
End Sub

- Zack

Answer 1

为了使命令工作，您需要在xaml或代码后面设置绑定。这些命令绑定必须引用先前声明的公共静态字段。

然后，在您的按钮Command属性中，您还需要引用这些相同的命令。

<Window 
    x:Class="RadioButtonCommandSample.Window1"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:local="clr-namespace:RadioButtonCommandSample"
    Title="Window1" 
    Height="300" 
    Width="300"
    >
    <Window.CommandBindings>
        <CommandBinding Command="{x:Static local:Window1.CommandOne}" Executed="CommandBinding_Executed"/>
        <CommandBinding Command="{x:Static local:Window1.CommandTwo}" Executed="CommandBinding_Executed"/>
        <CommandBinding Command="{x:Static local:Window1.CommandThree}" Executed="CommandBinding_Executed"/>
    </Window.CommandBindings>
    <StackPanel>
        <RadioButton Name="RadioButton1" GroupName="Buttons" Command="{x:Static local:Window1.CommandOne}" IsChecked="True">One</RadioButton>
        <RadioButton Name="RadioButton2" GroupName="Buttons" Command="{x:Static local:Window1.CommandTwo}">Two</RadioButton>
        <RadioButton Name="RadioButton3" GroupName="Buttons" Command="{x:Static local:Window1.CommandThree}">Three</RadioButton>
    </StackPanel>
</Window>

public partial class Window1 : Window
{
    public static readonly RoutedCommand CommandOne = new RoutedCommand();
    public static readonly RoutedCommand CommandTwo = new RoutedCommand();
    public static readonly RoutedCommand CommandThree = new RoutedCommand();

    public Window1()
    {
        InitializeComponent();
    }

    private void CommandBinding_Executed(object sender, ExecutedRoutedEventArgs e)
    {
        if (e.Command == CommandOne)
        {
            MessageBox.Show("CommandOne");
        }
        else if (e.Command == CommandTwo)
        {
            MessageBox.Show("CommandTwo");
        }
        else if (e.Command == CommandThree)
        {
            MessageBox.Show("CommandThree");
        }
    }
}

- Ian Oakes

---

我使用了这个，但当我加载页面时，我无法选择其中任何一个。有没有办法启用选择单选按钮？ - paradisonoir

我不确定问题可能是什么，我刚刚运行了这个示例，我能够顺利选择单选按钮。 - Ian Oakes

如果所有单选按钮都被禁用了，那么我的猜测是命令绑定失败了。 - Drew Noakes

Answer 2

使用WPF MVVM设计模式的更好解决方案：

将单选按钮控件XAML转换为Modelview.vb/ModelView.cs：

XAML Code:
<RadioButton Content="On" IsEnabled="True" IsChecked="{Binding OnJob}"/>
<RadioButton Content="Off" IsEnabled="True" IsChecked="{Binding OffJob}"/>

ViewModel.vb：

Private _OffJob As Boolean = False
Private _OnJob As Boolean = False

Public Property OnJob As Boolean
    Get
        Return _OnJob
    End Get
    Set(value As Boolean)
        Me._OnJob = value
    End Set
End Property

Public Property OffJob As Boolean
    Get
        Return _OffJob
    End Get
    Set(value As Boolean)
        Me._OffJob = value
    End Set
End Property

Private Sub FindCheckedItem()
  If(Me.OnJob = True)
    MessageBox.show("You have checked On")
 End If
If(Me.OffJob = False)
 MessageBox.Show("You have checked Off")
End sub

可以使用上述相同的逻辑来查看您是否选中了三个单选按钮之一，即选项一、选项二、选项三。但是，通过检查布尔值设置为true还是false，您可以确定单选按钮是否已选中。

- Sridhar Ganapathy