C# DependencyProperty的子属性上的样式触发器

我有一个控件，我想根据该控件的自定义

Message

类型

dependencProperty

的设置设置该控件的样式

自定义类型：

public class Message : ObservableObject
{
    public MessageTypes MessageType
    {
        get { return _messageType; }
        set {
            RaisePropertyChanged(() => MessageType);
            _messageType = value;
        } 
    }

    public string Text { ... }

    ...
}

public class MessageControl : Control
{
    public static readonly DependencyProperty MessageProperty =
        DependencyProperty.Register(
            "Message",
            typeof(Message),
            typeof(MessageControl),
            new FrameworkPropertyMetadata(null,
                FrameworkPropertyMetadataOptions.BindsTwoWayByDefault));

    public Message Message
    {
        get
        {
            return (Message)GetValue(MessageProperty);
        }
        set
        {
            SetValue(MessageProperty, value);
        }
    }
}

<ControlTemplate x:Key="MessageControlTemplate"
                 TargetType="controls:MessageControl">
    <Border Background="{TemplateBinding Background}">
        <TextBlock Text="{Binding Path=Message.Text,
                             RelativeSource={RelativeSource TemplatedParent}}" />
    </Border>
</ControlTemplate>

<Style TargetType="controls:MessageControl">
    <Setter Property="Template"
            Value="{StaticResource MessageControlTemplate}" />

    <Style.Triggers>
        <!-- HERE IS THE ISSUE -->
        <Trigger Property="Message.MessageType"
                 Value="{x:Static classes:MessageType.Error}">
            <Setter Property="Background" Value="Red" />
        </Trigger>
    </Style.Triggers>
</Style>

控制：

public class Message : ObservableObject
{
    public MessageTypes MessageType
    {
        get { return _messageType; }
        set {
            RaisePropertyChanged(() => MessageType);
            _messageType = value;
        } 
    }

    public string Text { ... }

    ...
}

public class MessageControl : Control
{
    public static readonly DependencyProperty MessageProperty =
        DependencyProperty.Register(
            "Message",
            typeof(Message),
            typeof(MessageControl),
            new FrameworkPropertyMetadata(null,
                FrameworkPropertyMetadataOptions.BindsTwoWayByDefault));

    public Message Message
    {
        get
        {
            return (Message)GetValue(MessageProperty);
        }
        set
        {
            SetValue(MessageProperty, value);
        }
    }
}

<ControlTemplate x:Key="MessageControlTemplate"
                 TargetType="controls:MessageControl">
    <Border Background="{TemplateBinding Background}">
        <TextBlock Text="{Binding Path=Message.Text,
                             RelativeSource={RelativeSource TemplatedParent}}" />
    </Border>
</ControlTemplate>

<Style TargetType="controls:MessageControl">
    <Setter Property="Template"
            Value="{StaticResource MessageControlTemplate}" />

    <Style.Triggers>
        <!-- HERE IS THE ISSUE -->
        <Trigger Property="Message.MessageType"
                 Value="{x:Static classes:MessageType.Error}">
            <Setter Property="Background" Value="Red" />
        </Trigger>
    </Style.Triggers>
</Style>

风格：

public class Message : ObservableObject
{
    public MessageTypes MessageType
    {
        get { return _messageType; }
        set {
            RaisePropertyChanged(() => MessageType);
            _messageType = value;
        } 
    }

    public string Text { ... }

    ...
}

public class MessageControl : Control
{
    public static readonly DependencyProperty MessageProperty =
        DependencyProperty.Register(
            "Message",
            typeof(Message),
            typeof(MessageControl),
            new FrameworkPropertyMetadata(null,
                FrameworkPropertyMetadataOptions.BindsTwoWayByDefault));

    public Message Message
    {
        get
        {
            return (Message)GetValue(MessageProperty);
        }
        set
        {
            SetValue(MessageProperty, value);
        }
    }
}

<ControlTemplate x:Key="MessageControlTemplate"
                 TargetType="controls:MessageControl">
    <Border Background="{TemplateBinding Background}">
        <TextBlock Text="{Binding Path=Message.Text,
                             RelativeSource={RelativeSource TemplatedParent}}" />
    </Border>
</ControlTemplate>

<Style TargetType="controls:MessageControl">
    <Setter Property="Template"
            Value="{StaticResource MessageControlTemplate}" />

    <Style.Triggers>
        <!-- HERE IS THE ISSUE -->
        <Trigger Property="Message.MessageType"
                 Value="{x:Static classes:MessageType.Error}">
            <Setter Property="Background" Value="Red" />
        </Trigger>
    </Style.Triggers>
</Style>

所以问题是我不能为

Message.MessageType

（或者基本上任何其他子属性）添加触发器

---

甚至有可能做到这一点吗？或者我应该在

MessageControl

中为

Text

和

MessageType

创建两个属性吗？

您可以使用DataTrigger执行此操作：

<Style TargetType="controls:MessageControl">
    ...
    <Style.Triggers>
        <DataTrigger Binding="{Binding Message.MessageType,
                               RelativeSource={RelativeSource Self}}"
                     Value="{x:Static classes:MessageType.Error}">
            <Setter Property="Background" Value="Red" />
        </DataTrigger>
    </Style.Triggers>
</Style>

---

谢谢你，真管用！关于PropertyChanged这件事，我只是想把它写出来，因为真正的代码有点复杂，但通常你对顺序的看法是正确的。