Question

我认为我有两个组合框。

我想要的是当我在ComboBox1上选择值1时，ComboBox2变为启用状态。但是，当我在ComboBox1中选择除1以外的任何其他值时，ComboBox2将保持禁用状态。

Answer 1

您的XAML：

<ComboBox x:Name="cb1" Margin="10,0" IsReadOnly="True" IsEditable="True" Text="Please select" HorizontalAlignment="Center" >
    <ComboBoxItem x:Name="cbi11" Content="Option1" HorizontalAlignment="Left" Width="198" Selected="cbi11_Selected" />
    <ComboBoxItem x:Name="cbi12" Content="Option2" HorizontalAlignment="Left" Width="198" Selected="cbi12_Selected"/>
    <ComboBoxItem x:Name="cbi13" Content="Option3" HorizontalAlignment="Left" Width="198" Selected="cbi13_Selected"/>
</ComboBox>

<ComboBox x:Name="cb2" Margin="10,0" IsReadOnly="True" IsEditable="True" Text="Please select" HorizontalAlignment="Center" >
    <ComboBoxItem x:Name="cbi21" Content="Option1" HorizontalAlignment="Left" Width="198" Selected="cbi21_Selected" />
    <ComboBoxItem x:Name="cbi22" Content="Option2" HorizontalAlignment="Left" Width="198" Selected="cbi22_Selected"/>
    <ComboBoxItem x:Name="cbi23" Content="Option3" HorizontalAlignment="Left" Width="198" Selected="cbi23_Selected"/>
</ComboBox>

你的守则背后：

private void cbi11_Selected(object sender, RoutedEventArgs e)
    { 
        cb2.IsEnabled = true;
    }
private void cbi12_Selected(object sender, RoutedEventArgs e)
    { 
        cb2.IsEnabled = false;
    }
private void cbi13_Selected(object sender, RoutedEventArgs e)
    { 
        cb2.IsEnabled = false;
    }

Answer 2

如果您正确地执行此操作，那么您提出错误的问题，因为您的视图模型将为您完成大部分工作

假设你有一个像这样的ViewModel（使用Prism）

public class VM:BindableBase
{
    public ICollectionView Combo1Options {get,set}
    public ICollectionView Combo2Options {get,set}

    private object _Combo1Value;
    private object _Combo2Value;

    public object Combo1Value 
    {
        get { return _Combo1Value; }
        set 
        {
            if(SetProperty(ref _Combo1Value, value))
            {
                Combo2Options .Refresh();
                PropertyChanged(nameof(Combo2Enabled));                    
            }
        }
    }

    public object Combo2Value 
    {
        get { return _Combo2Value; }
        set { SetProperty(ref _Combo2Value, value); }
    }
    public bool Combo2Enabled => Combo1Value != null;//or what ever logic defines if combo2 is required

}

然后你只需绑定到你的视图模型

<ComboBox ItemSource={Binding Combo1Options }, SelectedItem={Binding Combo1Value }/>
<ComboBox ItemSource={Binding Combo2Options }, SelectedItem={Binding Combo2Value } IsEnabled={Binding Combo2Enabled}/>

通过使用CollectionView，您可以过滤组合框项目，因此我会推荐它

WPF：根据另一个下拉列表中的值启用下拉列表

2 个答案: