如何才能最好地处理WPF单选按钮？

Question

我的XAML中有一些RadioButton ...

<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代码中处理他们的单击事件.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"
                'Do something one
                Exit Select
            Case "RadioButton2"
                'Do something two
                Exit Select
            Case "RadioButton3"
                'Do something three
                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).Command
            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

在我的XAML中,我在Command =属性上获得了一个蓝色波浪线下划线,这个提示......

'CommandValueSerializer' ValueSerializer cannot convert from 'System.String'.

在我的VB中,我在Select Case一行中得到一个绿色的波浪形下划线,这个警告......

Runtime errors might occur when converting 'System.Windows.Input.ICommand' to 'String'.

更好的方法是使用具有完整Intellisense的Enum类型命令并编译错误,而不是在打字错误的情况下运行时错误.我怎样才能改善这个？

Answer 1

为了使命令起作用,您需要在xaml或后面的代码中设置绑定.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");
        }
    }
}