31天重构指南之十五：移除重复内容

这是最常用的重构之一，我们经常要用到它，因为我们的代码中经常因为这或那的原因产生重复代码，让我们来看下面的例子：

   1: public class MedicalRecord

   2: {

   3:     public DateTime DateArchived { get; private set; }

   4:     public bool Archived { get; private set; }

   5:  

   6:     public void ArchiveRecord()

   7:     {

   8:         Archived = true;

   9:         DateArchived = DateTime.Now;

  10:     }

  11:  

  12:     public void CloseRecord()

  13:     {

  14:         Archived = true;

  15:         DateArchived = DateTime.Now;

  16:     }

  17: }

下面是我们重构后的代码，请记住只要有可能就请应用该重构，因为这可以帮你减少代码中的bug数量，另外请牢记DRY(don’t repeat yourself)原则，尽量不要复制/粘贴代码。

   1: public class MedicalRecord

   2: {

   3:     public DateTime DateArchived { get; private set; }

   4:     public bool Archived { get; private set; }

   5:  

   6:     public void ArchiveRecord()

   7:     {

   8:         SwitchToArchived();

   9:     }

  10:  

  11:     public void CloseRecord()

  12:     {

  13:         SwitchToArchived();

  14:     }

  15:  

  16:     private void SwitchToArchived()

  17:     {

  18:         Archived = true;

  19:         DateArchived = DateTime.Now;

  20:     }

  21: }

原文链接：http://www.lostechies.com/blogs/sean_chambers/archive/2009/08/15/refactoring-day-15-remove-duplication.aspx