Question

我创建了一个简单的场景来测试Polly，我可能完全错了。如果重试，则retries变量应为3。

请看看我做了什么。谢谢。

void Something(int Try)
        {
            try
            {
                if (Try <= 3)
                    throw new InvalidStudentNameException();

            }
            catch
            {

            }

        }
        protected void Button1_Click(object sender, EventArgs e)
        {
            int retries = 0;
            try
            {
                Something(retries);
                var Result = retries;
                var response = Policy
                    .Handle<InvalidStudentNameException>()
                    .Retry(3, (exception, attempt) =>
                    {
                        retries++;
                    })
                    .Execute
                    (() => Result);

                int reachable = response;
            }
            //catch (InvalidStudentNameException SSSS)
            //{

            //}
            finally
            {
                Response.Write(retries);
            }
        }

重试变量始终为零。那怎么办？。

Answer 1

在已发布的代码中，您对Something(retries)的呼叫不受重试策略的约束。这是一个简单的方法调用，在retries == 0时调用，并且立即抛出。

要使用用于管理对Something(...)的调用的策略，您需要在传递给Something(...)方法的委托中执行Execute(() => )。

示例中的Button1_Click(...)方法可以进行如下修改：

        protected void Button1_Click(object sender, EventArgs e)
        {
            int retries = 0;
            try
            {
                Action doSomething = () => Something(retries); // Creates an `Action` delegate which will be run by the retry policy.
                var response = Policy
                    .Handle<InvalidStudentNameException>()
                    .Retry(3, (exception, attempt) =>
                    {
                        retries++;
                    })
                    .Execute(doSomething); // Runs the action, ie executes Something(...), within the retry policy.

                int reachable = response;
            }
            //catch (InvalidStudentNameException SSSS)
            //{

            //}
            finally
            {
                Response.Write(retries);
            }
        }

（为了说明必要，我对代码进行了最小的更改。）

Polly不执行重试操作

1 个答案: