c# / WPF 在资源字典数据触发器中使用 c# 变量

Question

我正在使用一些带有模板内容的按钮

例如

button.Template = (ControlTemplate)FindResource("StatusEmpty");

在文件后面的同一代码中有一个名为 currentNumber 的（全局）字段

private int currentNumber = 1;
    public int CurrentNumber
    {
        get
        {
            return currentNumber;
        }
    }

这些模板在合并的 RessourceDictionary 中定义

<ControlTemplate x:Key="BinStatusEmpty" TargetType="Button">
    <Border x:Name="border"  BorderBrush="LightGray" CornerRadius="8,8,8,8" Margin="3" >
        <Border.Background>
            <LinearGradientBrush>
                <GradientStop Offset="0" Color="white"></GradientStop>
                <GradientStop Offset="1" Color="LightGray"></GradientStop>
            </LinearGradientBrush>
        </Border.Background>
        <ContentPresenter Content = "{TemplateBinding Content}" 
           HorizontalAlignment = "Center" VerticalAlignment = "Center"  
                             TextBlock.FontSize="40"/>
    </Border>
    <ControlTemplate.Triggers>
        <Trigger Property="IsMouseOver" Value="True">
            <Setter Property="BorderBrush" Value="Blue" TargetName="border" />
            <Setter Property="BorderThickness" Value="4" TargetName="border" />
        </Trigger>

        <DataTrigger Binding="{Binding currentNumber, RelativeSource={RelativeSource FindAncestor, AncestorType=Window}}" Value="{TemplateBinding Content}" >
            <Setter Property="BorderBrush" Value="Blue" TargetName="border" />
            <Setter Property="BorderThickness" Value="4" TargetName="border" />
        </DataTrigger>

    </ControlTemplate.Triggers>
</ControlTemplate>

我想要的是一个数据触发器，它根据当前c#变量改变模板动态中定义的边框。

目前有两个问题： 1）绑定

{Binding currentNumber, RelativeSource={RelativeSource FindAncestor, AncestorType=Window}}

找不到我的变量

BindingExpression path error: 'currentNumber' property not found on 'object' ''MainWindow' (Name='xMainWindow')'. BindingExpression:Path=currentNumber; DataItem='MainWindow' (Name='xMainWindow'); target element is 'BinButton' (Name=''); target property is 'NoTarget' (type 'Object')

2) 我无法绑定

{TemplateBinding Content}

作为数据触发器的值。

非常感谢

勒内

Answer 1

您应该绑定到属性 CurrentNumber（大写“C”）而不是支持字段currentNumber。

但是您不能将DataTrigger 的Value 属性绑定到某个东西。不支持：

Using binding for the Value property of DataTrigger condition

您需要使用转换器：

namespace WpfApplication1
{
    public class MultiConverter : IMultiValueConverter
    {
        public object Convert(object[] values, Type targetType, object parameter, CultureInfo culture)
        {
            int CurrentNumber = (int)values[0];
            object content = values[1];

            return CurrentNumber.ToString() == content.ToString();
        }

        public object[] ConvertBack(object value, Type[] targetTypes, object parameter, CultureInfo culture)
        {
            throw new NotSupportedException();
        }
    }
}

XAML：

<ControlTemplate x:Key="BinStatusEmpty" TargetType="Button"
                 xmlns:local="clr-namespace:WpfApplication1">
    <ControlTemplate.Resources>
        <local:MultiConverter x:Key="conv" />
    </ControlTemplate.Resources>
    <Border x:Name="border" BorderBrush="LightGray" CornerRadius="8,8,8,8" Margin="3" >
        <Border.Background>
            <LinearGradientBrush>
                <GradientStop Offset="0" Color="white"></GradientStop>
                <GradientStop Offset="1" Color="LightGray"></GradientStop>
            </LinearGradientBrush>
        </Border.Background>
        <ContentPresenter Content = "{TemplateBinding Content}" 
                                  HorizontalAlignment = "Center" VerticalAlignment = "Center"  
                                TextBlock.FontSize="40"/>
    </Border>
    <ControlTemplate.Triggers>
        <Trigger Property="IsMouseOver" Value="True">
            <Setter Property="BorderBrush" Value="Blue" TargetName="border" />
            <Setter Property="BorderThickness" Value="4" TargetName="border" />
        </Trigger>
        <DataTrigger Value="True">
            <DataTrigger.Binding>
                <MultiBinding Converter="{StaticResource conv}">
                    <Binding Path="CurrentNumber" RelativeSource="{RelativeSource FindAncestor, AncestorType=Window}" />
                    <Binding Path="Content" RelativeSource="{RelativeSource Self}" />
                </MultiBinding>
            </DataTrigger.Binding>
            <Setter Property="BorderBrush" Value="Blue" TargetName="border" />
            <Setter Property="BorderThickness" Value="4" TargetName="border" />
        </DataTrigger>
    </ControlTemplate.Triggers>
</ControlTemplate>