您可以创建自定义标记扩展,将样式属性和触发器合并为单个样式。您需要做的就是添加一个MarkupExtension
-派生类到您的命名空间MarkupExtensionReturnType
属性已定义,您就可以开始运行了。
这是一个扩展,允许您使用“类似 css”的语法合并样式。
多样式扩展.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];
}
}
然后,您的示例将通过以下方式解决:
<Style x:key="Combined" BasedOn="{local:MultiStyle A B}">
... other properties.
</Style>
我们通过在内置样式中合并其他两种样式“A”和“B”来定义一种名为“Combined”的新样式BasedOn
属性(用于样式继承)。我们可以选择像往常一样将其他属性添加到新的“组合”样式中。
其他例子:
在这里,我们定义了 4 种按钮样式,并且可以以各种组合方式使用它们,而无需重复:
<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" />
您甚至可以使用“.
" 语法将类型的“当前”默认样式(依赖于上下文)与一些附加样式合并:
<Button Style="{local:MultiStyle . GreenButtonStyle BoldButtonStyle}"/>
上面将合并默认样式TargetType="{x:Type Button}"
与两个补充样式。
Credit
我找到了最初的想法MultiStyleExtension
at bea.stollnitz.com https://web.archive.org/web/20120103082937/http://bea.stollnitz.com/blog/?p=384并修改它以支持“.
" 引用当前样式的符号。