Question

我想问一下，如何根据绑定变量的值选择Combobox项。例如，绑定布尔变量sex将值 true 绑定到 male ，将 false 绑定到 female ？

<ComboBox>
    <ComboBoxItem Content="male"/>        <- select if true
    <ComboBoxItem Content="female" />     <- select if false
</ComboBox>

Answer 1

试试这个例子：

<RadioButton Name="Female"
             Content="Female" 
             Margin="0,0,0,0" />

<RadioButton Name="Male"
             Content="Male"
             Margin="0,20,0,0" />

<ComboBox Width="100" Height="25">
    <ComboBoxItem Content="Male" 
                  IsSelected="{Binding Path=IsChecked, 
                                       ElementName=Male}" />           

    <ComboBoxItem Content="Female"
                  IsSelected="{Binding Path=IsChecked, 
                                       ElementName=Female}" />                
</ComboBox>

作为更通用的解决方案，您可以使用Converter：

提供了一种将自定义逻辑应用于绑定的方法。

示例：

XAML

<Window x:Class="MyNamespace.MainWindow"
        xmlns:this="clr-namespace:MyNamespace"

    <Window.Resources>
        <this:MaleFemaleConverter x:Key="MaleFemaleConverter" />
    </Window.Resources>

    <ComboBox Width="100" 
              Height="25"
              SelectedIndex="{Binding Path=IsChecked, <--- Here can be your variable
                                      ElementName=SomeElement, 
                                      Converter={StaticResource MaleFemaleConverter}}">

        <ComboBoxItem Content="Male" />
        <ComboBoxItem Content="Female" />                
    </ComboBox>

Code-behind

public class MaleFemaleConverter : IValueConverter    
{        
    public object Convert(object value, Type targetType, object parameter, CultureInfo culture)        
    {            
        bool Value = (bool)value;

        if (Value == true) 
        {
            return 1;
        }

        return 0;
    }

    public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
    {
        return DependencyProperty.UnsetValue; 
    }            
}

如何根据绑定变量的值选择ComboBox项？

1 个答案: