使用 DynamicProxy 从派生实例上的抽象父级拦截方法

Question

我有一个从抽象基类派生的对象，我想截取该对象的方法。

DynamicProxy 是否支持这种情况？我似乎只能通过接口或没有目标来创建代理，但不能通过抽象基类 with 一个目标

public abstract class Sandwich
{
    public abstract void ShareWithFriend();
}

public sealed class PastramiSandwich : Sandwich
{
    public override void ShareWithFriend()
    {
        throw new NotSupportedException("No way, dude");
    }
}

class SandwichInterceptor : IInterceptor
{
    public void Intercept(IInvocation invocation)
    {
        try
        {
            invocation.Proceed();
        }
        catch (NotSupportedException)
        {
            // too bad
        }
    }
}

internal class Program
{
    private static void Main()
    {
        var sandwich = new PastramiSandwich();
        var generator = new ProxyGenerator();

        // throws ArgumentException("specified type is not an interface")
        var proxy1 = generator.CreateInterfaceProxyWithTarget<Sandwich>(
            sandwich,
            new SandwichInterceptor());
        proxy1.ShareWithFriend();

        // does not accept a target
        var proxy2 = generator.CreateClassProxy<Sandwich>(
            /* sandwich?, */
            new SandwichInterceptor());
        // hence the method call fails in the interceptor
        proxy2.ShareWithFriend();
    }
}

Answer 1

这行得通：

var proxy1 = generator.CreateClassProxyWithTarget<Sandwich>(
    sandwich,
    new SandwichInterceptor());
proxy1.ShareWithFriend();