我的XAML出了什么问题?

sof*_*fun 1 c# wpf xaml

    <GroupBox x:Name="groupBox" Header="Operating System" HorizontalAlignment="Left" Margin="10,10,0,0" VerticalAlignment="Top" Height="74" Width="280">
        <RadioButton GroupName="Os" Content="Windows XP" IsChecked="True"/>
        <RadioButton GroupName="Os" Content="Windows Vista" />
        <RadioButton GroupName="Os" Content="Windows 7" />

    </GroupBox>
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我收到一条错误消息,说我无法多次设置内容.

我在WPF上使用C#

Mud*_*uds 6

组合框不是面板; 它只能有一个孩子.

尝试在其中使用堆栈面板/类似物:

<GroupBox x:Name="groupBox" Header="Operating System" HorizontalAlignment="Left" Margin="10,10,0,0" VerticalAlignment="Top" Height="74" Width="280">
    <StackPanel>
        <RadioButton GroupName="Os" Content="Windows XP" IsChecked="True"/>
        <RadioButton GroupName="Os" Content="Windows Vista" />
        <RadioButton GroupName="Os" Content="Windows 7" />
    </StackPanel>
</GroupBox>
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