重构这个嵌套在try/catch中的嵌套IF函数

Question

我有一个需要重构的混乱功能,它有太多嵌套的IF,它让我感到紧张只是看看它!

请忽略函数正在做什么,我更关心结构/流程以及它如何被重构,因此它具有较少的嵌套IF语句

基本流程如下:

public static void HandleUploadedFile(string filename)
{

      try
      {
        if(IsValidFileFormat(filename)
        {

            int folderID = GetFolderIDFromFilename(filename);

            if(folderID > 0)
            {

                if(HasNoViruses(filename)
                {

                    if(VerifyFileSize(filename)
                    {

                        // file is OK
                        MoveToSafeFolder(filename);

                    }
                    else
                    {
                        DeleteFile(filename);
                    }


                }
                else
                {
                    DeleteFile(filename);
                }


            }
            else
            {
                DeleteFile(filename);
            }



        }
        else
        {
            DeleteFile(filename);
        }
      }
      catch (Exception ex)
      {

      }
      finally
      {
        // do some things
      }


}

Answer 1

我很想去:

    private static bool CanMoveToSafeFolder(string filename)
    {
        return IsValidFileFormat(filename)
            && GetFolderIDFromFilename(filename) > 0
            && HasNoViruses(filename)
            && VerifyFileSize(filename);
    }

    public static void HandleUploadedFile(string filename)
    {

        try
        {

            if (CanMoveToSafeFolder(filename))
            {
                // file is OK
                MoveToSafeFolder(filename);
            }
            else
            {
                DeleteFile(filename);
            }
        }
        catch (Exception ex)
        {

        }
        finally
        {
            // do some things
        }

    }