获取组中所选单选按钮的索引

时间:2013-06-13 08:28:22

标签: c# wpf radio-button visualtreehelper

我有一个RadioButton rb1的引用 如何在rb1的组中获取所选RadioButton的索引?
我用google搜索了一段时间但没有成功。

非常感谢任何帮助

2 个答案:

答案 0 :(得分:1)

你的问题很简短,你不是。您应该做的是将RadioButton.IsChecked绑定到视图模型的某个bool属性。您可以通过int的实现来绑定视图模型的IValueConverter属性来实现组索引之类的功能:

查看模型属性:

private int _groupIndex = 1;

public int GroupIndex
{
   get { return _groupIndex; }
   set
   {
       if (_groupIndex == value) return;
       _groupIndex = value;
       OnPropertyChanged("GroupIndex");
   }
}

转换器:

public class IndexBooleanConverter : IValueConverter
{
  public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
  {
      if (value == null || parameter == null)
          return false;
      else
          return (int)value == System.Convert.ToInt32(parameter);
  }

  public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
  {
      if (value == null || parameter == null)
          return null;
      else if ((bool)value)
          return System.Convert.ToInt32(parameter);
      else
          return DependencyProperty.UnsetValue;
  }
}   

然后你像这样绑定它:

<StackPanel Orientation="Horizontal">
   <StackPanel.Resources>
       <local:IndexBooleanConverter x:Key="IndexBooleanConverter"/>
   </StackPanel.Resources>
   <RadioButton Content="Option1" IsChecked="{Binding Path=GroupIndex, Converter={StaticResource IndexBooleanConverter}, ConverterParameter=1}"/>
   <RadioButton Content="Option2" IsChecked="{Binding Path=GroupIndex, Converter={StaticResource IndexBooleanConverter}, ConverterParameter=2}"/>
   <RadioButton Content="Option3" IsChecked="{Binding Path=GroupIndex, Converter={StaticResource IndexBooleanConverter}, ConverterParameter=3}"/>
</StackPanel>

在这种情况下,您的视图模型属性GroupIndex将具有值1,2或3,具体取决于勾选的RadioButton

答案 1 :(得分:0)

如果你到了这一点,那么你的设计可能有问题,你应该重新考虑它。

据说你可以遍历视觉树并找到它:

        /// Returns the first GroupBox ancester            
        public DependencyObject  FindAncestor(DependencyObject current)

        {
            current = VisualTreeHelper.GetParent(current);

            while (current != null)
            {
                if (current is GroupBox)
                {
                    return (T)current;
                }
                current = VisualTreeHelper.GetParent(current);
            };
            return null;
        }

然后仔细检查孩子们并找到已检查的radioButton

    public RadioButton FindChild<T>(DependencyObject parent)       
    {
        // Confirm parent and childName are valid.
        if (parent == null) return null;

        RadioButton foundChild = null;

        int childrenCount = VisualTreeHelper.GetChildrenCount(parent);
        for (int i = 0; i < childrenCount; i++)
        {
            var child = VisualTreeHelper.GetChild(parent, i);
            // If the child is not of the request child type child
            var childType = child as radioButton;
            if (childType == null)
            {
                // recursively drill down the tree
                foundChild = FindChild(child);

                // If the child is found, break so we do not overwrite the found child.
                if (foundChild != null) return foundChild ;
            }
            else if (childName.IsChecked == true)
            {
               return foundChild;  
            }
        }

        return null;
    }