WPF（多样式）

XAML能不能像HTML一样可以对元素应用多个样式呢？？？默认的情况下是不可以的，下面将讲述两种通过其他方法实现同时应用多个样式的例子。

1.BasedOn

 通过继承相当于拥有两种样式。 

<Window x:Class="WpfAppLearn2.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:WpfAppLearn2"
        xmlns:ms="clr-namespace:WpfMultiStyle;assembly=WpfMultiStyle"
        mc:Ignorable="d"
        Title="MainWindow" Height="450" Width="319" Background="#FFD4D2D2" WindowStartupLocation="CenterScreen">
    <Canvas HorizontalAlignment="Left" VerticalAlignment="Top">
        <Canvas.Resources>
            <Style x:Key="tbStyle1" TargetType="TextBox">
                <Setter Property="Background" Value="Maroon"/>
                <Style.Triggers>
                    <Trigger Property="Text" Value="123">
                        <Setter Property="Foreground" Value="Chocolate"/>
                    </Trigger>
                </Style.Triggers>
            </Style>
            <Style x:Key="tbStyle2" TargetType="TextBox" BasedOn="{StaticResource tbStyle1}">
                <Setter Property="Background" Value="Gold"/>
                <Style.Triggers>
                    <Trigger Property="Text" Value="123">
                        <Setter Property="Foreground" Value="Green"/>
                    </Trigger>
                </Style.Triggers>
            </Style>
        </Canvas.Resources>
        <TextBox Height="23" Style="{StaticResource tbStyle2}" Text="C#" Width="120" Canvas.Left="65" Canvas.Top="235"/>
        <Button Content="Button" Width="75"/>
    </Canvas>
</Window>

2. WpfMultiStyle

NuGet搜索安装WpfMultiStyle： 

<Window x:Class="WpfAppLearn2.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:WpfAppLearn2"
        xmlns:ms="clr-namespace:WpfMultiStyle;assembly=WpfMultiStyle"
        mc:Ignorable="d"
        Title="MainWindow" Height="450" Width="319" Background="#FFD4D2D2" WindowStartupLocation="CenterScreen">
    <Canvas HorizontalAlignment="Left" VerticalAlignment="Top">
        <Canvas.Resources>
            <Style x:Key="tbStyle1" TargetType="TextBox">
                <Setter Property="Background" Value="Maroon"/>
                <Style.Triggers>
                    <Trigger Property="Text" Value="123">
                        <Setter Property="Foreground" Value="Chocolate"/>
                    </Trigger>
                </Style.Triggers>
            </Style>
            <Style x:Key="tbStyle2" TargetType="TextBox">
                <Setter Property="Background" Value="Gold"/>
                <Style.Triggers>
                    <Trigger Property="Text" Value="123">
                        <Setter Property="Foreground" Value="Green"/>
                    </Trigger>
                </Style.Triggers>
            </Style>
        </Canvas.Resources>
        <TextBox Height="23" Style="{ms:MultiStyle tbStyle2 tbStyle1 }" Text="C#" Width="120" Canvas.Left="65" Canvas.Top="235"/>
        <Button Content="Button" Width="75"/>
    </Canvas>
</Window>

引用名称空间：xmlns:ms="clr-namespace:WpfMultiStyle;assembly=WpfMultiStyle" 

就可以应用多样式了：TextBox Height="23" Style="{ms:MultiStyle tbStyle2 tbStyle1 }"

多样式应用相当于依次应用样式，所以同样的属性设置，最后一次有效。