Question

我正在使用Ninject和AOP进行缓存。我有一个属性，我可以应用于我的存储库中的任何方法和BeforeInvoke它将返回我的缓存对象，如果有一个和AfterInvoke创建一个缓存的对象。这一切都很好，但我无法弄清楚如何停止调用初始方法，即如果有一个缓存的对象返回而不是调用intyercepted方法。我的拦截器在这里：

public class CacheInterceptor : SimpleInterceptor
{
    protected override void BeforeInvoke(IInvocation invocation)
    {
        Type returnType = invocation.Request.Method.ReturnType;
        string cacheKey = CacheKeyBuilder.GetCacheKey(invocation, serializer);
        object cachedValue = cache.Get(cacheKey);
        if (cachedValue == null)
        {
            invocation.Proceed();
        }
        else
        {
            object returnValue = serializer.Deserialize(returnType, cachedValue);
            invocation.ReturnValue = returnValue;
            returnedCachedResult = true;
        }
     }
}

即使在else语句中我显然没有说要调用被调用的方法'invocation.Proceed（）;'它仍然会调用它。如何告诉ninject只返回invocation.ReturnValue？

Answer 1

在这种情况下，您不能使用SimpleInterceptor，因为这是您希望在实际方法调用之前或之后执行操作的最常见方案的基类。此外，您无法致电Proceed而是实施IInterceptor界面，并将您的代码放入Intercept方法。

但是我们可能会在将来的版本中扩展SimpleInterceptor，以便您可以阻止调用实际方法：

public abstract class SimpleInterceptor : IInterceptor
{
    private bool proceedInvocation = true;

    /// <summary>
    /// Intercepts the specified invocation.
    /// </summary>
    /// <param name="invocation">The invocation to intercept.</param>
    public void Intercept( IInvocation invocation )
    {
        BeforeInvoke( invocation );
        if (proceedInvocation)
        {
            invocation.Proceed();
            AfterInvoke( invocation );
        }
    }

    /// <summary>
    /// When called in BeforeInvoke then the invokation in not proceeded anymore.
    /// Or in other words the decorated method and AfterInvoke won't be called anymore.
    /// Make sure you have assigned the return value in case it is not void.
    /// </summary>
    protected void DontProceedInvokation()
    {
        this.proceedInvocation = false;
    }

    /// <summary>
    /// Takes some action before the invocation proceeds.
    /// </summary>
    /// <param name="invocation">The invocation that is being intercepted.</param>
    protected virtual void BeforeInvoke( IInvocation invocation )
    {
    }

    /// <summary>
    /// Takes some action after the invocation proceeds.
    /// </summary>
    /// <param name="invocation">The invocation that is being intercepted.</param>
    protected virtual void AfterInvoke( IInvocation invocation )
    {
    }
}

AOP Ninject停止拦截方法被调用

1 个答案: