月更

AntDesignWPF/Converters/GenericConverterExtension.cs

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+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using System.Windows.Data;
+using System.Windows.Markup;
+
+namespace AntDesign.WPF.Converters;
+
+/// <summary>
+/// 构造单例的Converter的markup
+/// </summary>
+/// <example>
+/// 示例代码：
+/// <code>
+/// <![CDATA[<TextBlock Text="{Binding Value, Converter={local:GenericConverterExtension Type={x:Type local:MyValueConverter}}}" />]]>
+/// </code>
+/// </example>
+public class GenericConverterExtension : MarkupExtension
+{
+    public Type Type { get; set; }
+
+    private static readonly Dictionary<Type, object> _instances = new();
+    public override object ProvideValue(IServiceProvider serviceProvider)
+    {
+        if (Type == null || !typeof(IValueConverter).IsAssignableFrom(Type)|| !typeof(IMultiValueConverter).IsAssignableFrom(Type))
+            throw new InvalidOperationException("类型必须是值转换器");
+
+        if (!_instances.TryGetValue(Type, out var instance))
+            _instances[Type] = instance = Activator.CreateInstance(Type);
+
+        return instance;
+    }
+}
+