c# - 具有多个返回点的重构方法

Question

**编辑:下面有几个可行的选项。请根据您对此事的看法进行投票/评论。

我正在清理并向具有以下基本结构的 c# 方法添加功能:

    public void processStuff()
    {
        Status returnStatus = Status.Success;
        try
        {
            bool step1succeeded = performStep1();
            if (!step1succeeded)
                return Status.Error;

            bool step2suceeded = performStep2();
            if (!step2suceeded)
                return Status.Warning;

            //.. More steps, some of which could change returnStatus..//

            bool step3succeeded = performStep3();
            if (!step3succeeded)
                return Status.Error;
        }
        catch (Exception ex)
        {
            log(ex);
            returnStatus = Status.Error;
        }
        finally
        {
            //some necessary cleanup
        }

        return returnStatus;
    }

有很多步骤，在大多数情况下，步骤 x 必须成功才能继续执行步骤 x+1。现在，我需要添加一些始终在方法结束时运行的功能，但它取决于返回值。我正在寻找有关如何彻底重构它以达到预期效果的建议。显而易见的选择是将依赖于返回值的功能放在调用代码中，但我无法修改调用方。

一个选项:

    public void processStuff()
    {
        Status returnStatus = Status.Success;
        try
        {
            bool step1succeeded = performStep1();
            if (!step1succeeded)
            {
                returnStatus =  Status.Error;
                throw new Exception("Error");
            }

            bool step2succeeded = performStep2();
            if (!step2succeeded)
            {
                returnStatus =  Status.Warning;
                throw new Exception("Warning");
            }

            //.. the rest of the steps ..//
        }
        catch (Exception ex)
        {
            log(ex);
        }
        finally
        {
            //some necessary cleanup
        }
        FinalProcessing(returnStatus);
        return returnStatus;
    }

我觉得这有点难看。相反，我可以直接从 performStepX() 方法中抛出。但是，这留下了在 processStuff() 的 catch block 中适当设置 returnStatus 变量的问题。您可能已经注意到，处理步骤失败时返回的值取决于失败的步骤。

    public void processStuff()
    {
        Status returnStatus = Status.Success;
        try
        {
            bool step1succeeded = performStep1(); //throws on failure
            bool step2succeeded = performStep2(); //throws on failure

            //.. the rest of the steps ..//
        }
        catch (Exception ex)
        {
            log(ex);
            returnStatus = Status.Error;  //This is wrong if step 2 fails!
        }
        finally
        {
            //some necessary cleanup
        }
        FinalProcessing(returnStatus);
        return returnStatus;
    }

如果您有任何建议，我将不胜感激。

Answer 1

不要使用异常来控制程序的流程。就个人而言，我会保留代码原样。要在最后添加新功能，您可以这样做:

    public void processStuff()
    {
        Status returnStatus = Status.Success;
        try
        {
            if (!performStep1())
                returnStatus = Status.Error;
            else if (!performStep2())
                returnStatus = Status.Warning;

            //.. More steps, some of which could change returnStatus..//

            else if (!performStep3())
                returnStatus = Status.Error;
        }
        catch (Exception ex)
        {
            log(ex);
            returnStatus = Status.Error;
        }
        finally
        {
            //some necessary cleanup
        }

        // Do your FinalProcessing(returnStatus);

        return returnStatus;
    }