binding radiobuttons group to a property in WPF

问题

Let's imagine that I have:

<RadioButton GroupName="Group1" IsChecked="{Binding Path=RadioButton1IsChecked}" />
<RadioButton GroupName="Group1" IsChecked="{Binding Path=RadioButton2IsChecked}" />

And then in my data source class I have:

public bool RadioButton1IsChecked { get; set; }
public bool RadioButton2IsChecked { get; set; }
public enum RadioButtons { RadioButton1, RadioButton2, None }
public RadioButtons SelectedRadioButton
{
    get
    {
        if (this.RadioButtonIsChecked) 
            return RadioButtons.RadioButton1;
        else if (this.RadioButtonIsChecked) 
            return RadioButtons.RadioButton2;
        else 
            return RadioButtons.None;
     }
}

Can I somehow bind my radio buttons directly to SelectedRadioButton property? I really need RadioButton1IsChecked and RadioButton2IsChecked properties only to calculate the selected radiobutton.

回答1:

Declare an enumeration similar to:

enum RadioOptions {Option1, Option2}

XAML:

<RadioButton IsChecked="{Binding SelectedOption, Converter={StaticResource EnumBooleanConverter}, ConverterParameter={x:Static local:RadioOptions.Option1}}"/>
<RadioButton IsChecked="{Binding SelectedOption, Converter={StaticResource EnumBooleanConverter}, ConverterParameter={x:Static local:RadioOptions.Option2}}"/>

Converter class:

public class EnumBooleanConverter : IValueConverter
{
    public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
    {
        return value.Equals(parameter);
    }

    public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
    {
        return ((bool)value) ? parameter : Binding.DoNothing;
    }
}

回答2:

<RadioButton GroupName="Group1" IsChecked="{Binding Path=SelectedRadioButton, Converter={StaticResource EnumBooleanConverter}, ConverterParameter=RadioButton1}" />
<RadioButton GroupName="Group1" IsChecked="{Binding Path=SelectedRadioButton, Converter={StaticResource EnumBooleanConverter}, ConverterParameter=RadioButton2}" />

public enum RadioButtons { RadioButton1, RadioButton2, None }
public RadioButtons SelectedRadioButton {get;set;}

 public class EnumBooleanConverter : IValueConverter
    {
        public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
        {
            var ParameterString = parameter as string;
            if (ParameterString == null)
                return DependencyProperty.UnsetValue;

            if (Enum.IsDefined(value.GetType(), value) == false)
                return DependencyProperty.UnsetValue;

            object paramvalue = Enum.Parse(value.GetType(), ParameterString);
            return paramvalue.Equals(value);
        }

        public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
        {
            var ParameterString = parameter as string;
            var valueAsBool = (bool) value;

            if (ParameterString == null || !valueAsBool)
            {
                try
                {
                    return Enum.Parse(targetType, "0");
                }
                catch (Exception)
                {
                    return DependencyProperty.UnsetValue;
                }
            }
            return Enum.Parse(targetType, ParameterString);
        }
    }

回答3:

XAML:

<RadioButton IsChecked="{Binding Path=SelectedOption, UpdateSourceTrigger=PropertyChanged}">Option1</RadioButton>
<RadioButton IsChecked="{Binding Path=SelectedOption, UpdateSourceTrigger=PropertyChanged, Converter={v:NotBoolenConverter}}">Option2</RadioButton>

Converter:

public class NotBoolenConverter : IValueConverter
    {
        public NotBoolenConverter()
        {
        }

        public override object Convert(
            object value,
            Type targetType,
            object parameter,
            CultureInfo culture)
        {
            bool output = (bool)value;
            return !output;
        }

        public override object ConvertBack(
            object value,
            Type targetType,
            object parameter,
            CultureInfo culture)
        {
            bool output = (bool)value;
            return !output;
        }
    }

Works with 2 radio buttons, by binding one to the opposite of the other.

来源：https://stackoverflow.com/questions/9212873/binding-radiobuttons-group-to-a-property-in-wpf