有没有一种方法可以将多个XAML样式合并成一个新的样式，其中包含所有所需的设置？
例如（伪代码）;
<Style x:key="A">
...
</Style>
<Style x:key="B">
...
</Style>
<Style x:key="Combined">
<IncludeStyle Name="A"/>
<IncludeStyle Name="B"/>
... other properties.
</Style>
我知道样式有一个BasedOn属性，但是这个功能不能满足我的需求。我真的只是在寻找一种简单的方式（在XAML中）来创建这些“组合”样式。但就像我之前说过的，我怀疑这种东西是否存在，除非有人听说过这样的事情？
您可以创建自定义的标记扩展，将样式属性和触发器合并为一个单独的样式。您只需要向您的命名空间添加一个MarkupExtension-派生类，并定义MarkupExtensionReturnType属性，然后就可以开始运行了。
这是一个扩展，它将允许您使用“类似于css”的语法合并样式。
MultiStyleExtension.cs
[MarkupExtensionReturnType(typeof(Style))]
public class MultiStyleExtension : MarkupExtension
{
private string[] resourceKeys;
/// <summary>
/// Public constructor.
/// </summary>
/// <param name="inputResourceKeys">The constructor input should be a string consisting of one or more style names separated by spaces.</param>
public MultiStyleExtension(string inputResourceKeys)
{
if (inputResourceKeys == null)
throw new ArgumentNullException("inputResourceKeys");
this.resourceKeys = inputResourceKeys.Split(new char[] { ' ' }, StringSplitOptions.RemoveEmptyEntries);
if (this.resourceKeys.Length == 0)
throw new ArgumentException("No input resource keys specified.");
}
/// <summary>
/// Returns a style that merges all styles with the keys specified in the constructor.
/// </summary>
/// <param name="serviceProvider">The service provider for this markup extension.</param>
/// <returns>A style that merges all styles with the keys specified in the constructor.</returns>
public override object ProvideValue(IServiceProvider serviceProvider)
{
Style resultStyle = new Style();
foreach (string currentResourceKey in resourceKeys)
{
object key = currentResourceKey;
if (currentResourceKey == ".")
{
IProvideValueTarget service = (IProvideValueTarget)serviceProvider.GetService(typeof(IProvideValueTarget));
key = service.TargetObject.GetType();
}
Style currentStyle = new StaticResourceExtension(key).ProvideValue(serviceProvider) as Style;
if (currentStyle == null)
throw new InvalidOperationException("Could not find style with resource key " + currentResourceKey + ".");
resultStyle.Merge(currentStyle);
}
return resultStyle;
}
}
public static class MultiStyleMethods
{
/// <summary>
/// Merges the two styles passed as parameters. The first style will be modified to include any
/// information present in the second. If there are collisions, the second style takes priority.
/// </summary>
/// <param name="style1">First style to merge, which will be modified to include information from the second one.</param>
/// <param name="style2">Second style to merge.</param>
public static void Merge(this Style style1, Style style2)
{
if(style1 == null)
throw new ArgumentNullException("style1");
if(style2 == null)
throw new ArgumentNullException("style2");
if(style1.TargetType.IsAssignableFrom(style2.TargetType))
style1.TargetType = style2.TargetType;
if(style2.BasedOn != null)
Merge(style1, style2.BasedOn);
foreach(SetterBase currentSetter in style2.Setters)
style1.Setters.Add(currentSetter);
foreach(TriggerBase currentTrigger in style2.Triggers)
style1.Triggers.Add(currentTrigger);
// This code is only needed when using DynamicResources.
foreach(object key in style2.Resources.Keys)
style1.Resources[key] = style2.Resources[key];
}
}
你的示例可以通过以下方式解决：
<Style x:key="Combined" BasedOn="{local:MultiStyle A B}">
... other properties.
</Style>
我们通过合并两种其他样式“A”和“B”，在内置的BasedOn属性（用于样式继承）中定义了一个名为“Combined”的新样式。按照惯例，我们可以选择向新的“Combined”样式添加其他属性。
其他示例:
这里，我们定义了4个按钮样式，并可以以各种组合方式使用它们，减少了重复：
<Window.Resources>
<Style TargetType="Button" x:Key="ButtonStyle">
<Setter Property="Width" Value="120" />
<Setter Property="Height" Value="25" />
<Setter Property="FontSize" Value="12" />
</Style>
<Style TargetType="Button" x:Key="GreenButtonStyle">
<Setter Property="Foreground" Value="Green" />
</Style>
<Style TargetType="Button" x:Key="RedButtonStyle">
<Setter Property="Foreground" Value="Red" />
</Style>
<Style TargetType="Button" x:Key="BoldButtonStyle">
<Setter Property="FontWeight" Value="Bold" />
</Style>
</Window.Resources>
<Button Style="{local:MultiStyle ButtonStyle GreenButtonStyle}" Content="Green Button" />
<Button Style="{local:MultiStyle ButtonStyle RedButtonStyle}" Content="Red Button" />
<Button Style="{local:MultiStyle ButtonStyle GreenButtonStyle BoldButtonStyle}" Content="green, bold button" />
<Button Style="{local:MultiStyle ButtonStyle RedButtonStyle BoldButtonStyle}" Content="red, bold button" />
你甚至可以使用 "." 语法将一些附加样式与某种类型（上下文相关）的“当前”默认样式合并：
<Button Style="{local:MultiStyle . GreenButtonStyle BoldButtonStyle}"/>
TargetType="{x:Type Button}" 是指按钮类型。
鸣谢：我在bea.stollnitz.com上找到了MultiStyleExtension的原始想法，并对其进行了修改，以支持“.”符号用于引用当前样式。IProvideValueTarget service = (IProvideValueTarget)serviceProvider.GetService(typeof(IProvideValueTarget)); if (service.TargetObject is Style) { key = ((Style)service.TargetObject).TargetType; } else { key = service.TargetObject.GetType(); } - MoonStom<Style x:Key="BaseButtons" TargetType="{x:Type Button}">
<Setter Property="BorderThickness" Value="0"></Setter>
<Setter Property="Background" Value="Transparent"></Setter>
<Setter Property="Cursor" Value="Hand"></Setter>
<Setter Property="VerticalAlignment" Value="Center"></Setter>
</Style>
<Style x:Key="ManageButtons" TargetType="{x:Type Button}" BasedOn="{StaticResource BaseButtons}">
<Setter Property="Height" Value="50"></Setter>
<Setter Property="Width" Value="50"></Setter>
</Style>
<Style x:Key="ManageStartButton" TargetType="{x:Type Button}" BasedOn="{StaticResource BaseButtons}">
<Setter Property="FontSize" Value="16"></Setter>
</Style>
并使用：
<Button Style="{StaticResource ManageButtons}"></Button>
<Button Style="{StaticResource ManageStartButton}"></Button>