Silverlight - 單選按鈕

RadioButton（單選按鈕）是一種按鈕，允許使用者從一組選項中選擇一個選項。使用者只能從相關的選項列表中選擇一個選項，這些選項是互斥的。它只有兩個選項：

• 選中
• 清除

RadioButton 也派生自 ToggleButton，並使用相同的 IsChecked 屬性以及相同的 Checked、Unchecked 和 Indeterminate 事件。除此之外，RadioButton 還添加了一個名為 GroupName 的屬性，允許您控制單選按鈕如何分組。

• 通常，單選按鈕由其容器分組。這意味著，如果您將三個 RadioButton 控制元件放置在一個 StackPanel 中，它們將形成一個組，從中您只能選擇三個中的一個。

• 另一方面，如果您將單選按鈕的組合放置在兩個單獨的 StackPanel 控制元件中，則您將有兩個獨立的組。

RadioButton 類的層次繼承如下：

以下是 RadioButton 最常用的屬性。

以下是 RadioButton 最常用的方法。

以下是 RadioButton 最常用的事件。

示例

讓我們來看一個簡單的示例，其中包含不同的按鈕。

<UserControl x:Class = "Buttons.MainPage" 
   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" 
   mc:Ignorable = "d" 
   d:DesignHeight = "300" d:DesignWidth = "400"> 
	
   <StackPanel x:Name = "LayoutRoot" Background = "White"> 
      <Button x:Name = "button" Content = "Click Me" HorizontalAlignment = "Left"  
         Margin = "10" VerticalAlignment = "Top" Width = "75"/>
			
      <StackPanel> 
		
         <Border Margin = "5" Padding = "5" BorderBrush = "Yellow" BorderThickness = "1" 
            CornerRadius = "5"> 
				
            <StackPanel>
               <RadioButton Content = "Group 1"/> 
               <RadioButton Content = "Group 1"/> 
               <RadioButton Content = "Group 1"/>
               <RadioButton GroupName = "Group3" Content = "Group 3"/>
            </StackPanel> 
				
         </Border>
			
         <Border Margin = "5" Padding = "5" BorderBrush = "Yellow" BorderThickness = "1" 
            CornerRadius = "5"> 
				
            <StackPanel>
               <RadioButton Content = "Group 2"/> 
               <RadioButton Content = "Group 2"/> 
               <RadioButton Content = "Group 2"/>
               <RadioButton GroupName = "Group3" Content = "Group 3"/>
            </StackPanel>
         </Border>
			
      </StackPanel> 
		
      <CheckBox x:Name = "checkBox1" Content = "Two States" HorizontalAlignment = "Left"  
         VerticalAlignment = "Top" Checked = "HandleCheck" Margin = "10,0,0,0" 
         Unchecked = "HandleUnchecked" Width = "90"/> 
			
      <CheckBox x:Name = "checkBox2" Content = "Three States" HorizontalAlignment = "Left"  
         VerticalAlignment = "Top" Width = "90" IsThreeState = "True" Margin = "10,0,0,0" 
         Indeterminate = "HandleThirdState" Checked = "HandleCheck" 
         Unchecked = "HandleUnchecked"/>
			
      <TextBox x:Name = "textBox1" HorizontalAlignment = "Left" Margin = "10,0,0,0" 
         TextWrapping = "Wrap" VerticalAlignment = "Top" Width = "300"/>
			
      <TextBox x:Name = "textBox2" HorizontalAlignment = "Left" 
         Margin = "10,0,0,0" Height = "23" TextWrapping = "Wrap" 
         VerticalAlignment = "Top" Width = "300"/>
			
   </StackPanel>
	
</UserControl>

這裡有兩個容器包含單選按鈕，但有三個組。每個組框底部的最後一個單選按鈕是第三個組的一部分。還有兩個狀態和三個狀態的複選框。

以下是 事件實現 的 C# 程式碼。

using System.Windows; 
using System.Windows.Controls;  

namespace Buttons { 

   public partial class MainPage : UserControl { 
	
      public MainPage() { 
         InitializeComponent(); 
      } 
		
      private void HandleCheck(object sender, RoutedEventArgs e) { 
         CheckBox cb = sender as CheckBox; 
			
         if (cb.Name == "checkBox1") textBox1.Text = "2 state CheckBox is checked."; 
         else textBox2.Text = "3 state CheckBox is checked."; 
      } 
		
      private void HandleUnchecked(object sender, RoutedEventArgs e) { 
         CheckBox cb = sender as CheckBox;
			
         if (cb.Name == "checkBox1") textBox1.Text = "2 state CheckBox is unchecked."; 
         else textBox2.Text = "3 state CheckBox is unchecked."; 
      }  
		
      private void HandleThirdState(object sender, RoutedEventArgs e) { 
         CheckBox cb = sender as CheckBox; 
         textBox2.Text = "3 state CheckBox is in indeterminate state."; 
      } 
		
   } 
}

當編譯並執行上述程式碼時，將顯示以下網頁。