一、Extract Class（提炼类）
动机（Motivation）
一个class应该是一个清楚的抽象（abstract），处理一些明确的责任。但在实际工作中，class会不断成长扩展。这个class会变得过份复杂，很快，class就会变成一团乱麻。
示例
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private string _officeAreaCode; |
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private string _officeNumber; |
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set { _name = value; } |
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public string OfficeAreaCode |
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get { return _officeAreaCode; } |
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set { _officeAreaCode = value; } |
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public string OfficeNumber |
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get { return _officeNumber; } |
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set { _officeNumber = value; } |
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public string TelephoneNumber |
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get { return "(" + _officeAreaCode + ")" + _officeNumber; } |
改为
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private Telephone _telephoneNumber; |
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public Telephone TelephoneNumber |
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get { return _telephoneNumber; } |
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set { _telephoneNumber = value; } |
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set { _name = value; } |
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public string TemphoneNumber |
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get { return _telephoneNumber.TelephoneNumber; } |
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public class Telephone |
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private string _officeAreaCode; |
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private string _officeNumber; |
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public string OfficeAreaCode |
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get { return _officeAreaCode; } |
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set { _officeAreaCode = value; } |
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public string OfficeNumber |
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get { return _officeNumber; } |
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set { _officeNumber = value; } |
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public string TelephoneNumber |
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get { return "(" + _officeAreaCode + ")" + _officeNumber; } |
二、Inline Class（将类内联化）
动机（Motivation）
一个class不再承担足够责任、不再有单独存在的理由，将class的所有特性搬移到另一个class中，然后移除原class。
示例
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set { _name = value; } |
改为
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set { _name = value; } |
三、Hide Delegate（隐藏[委托关系]）
动机（Motivation）
[封装]即使不是对象的最关键特征，也是最关键特征之一。[封装]意味每个对象都应该尽可能少了解系统的其它部分。如此一来，一旦发生变化，需要了解这变化的对象就会比较少，这会使谈化比较容易进行。
示例
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private Department _depart; |
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set { _name = value; } |
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public Department Depart |
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get { return _depart; } |
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set { _depart = value; } |
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public class Department |
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private string _departName; |
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private User _manager; |
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public string DepartName |
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get { return _departName; } |
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set { _departName = value; } |
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get { return _manager; } |
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set { _manager = value; } |
改为
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private Department _depart; |
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set { _name = value; } |
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public Department Depart |
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get { return _depart; } |
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set { _depart = value; } |
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public string DepartmentManager |
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get { return _depart.Manager; } |
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public class Department |
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private string _departName; |
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private User _manager; |
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public string DepartName |
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get { return _departName; } |
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set { _departName = value; } |
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get { return _manager; } |
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set { _manager = value; } |
这样取部门管理者就更直接，更方便，适合于少量使用。
但如果有大量的方法都用到了DepartmentManager里，我们就要去掉中间人了。
四、Remove Middle Man（移除中间人）
动机（Motivation）
大量重复的代码是万恶之源。这些重复性代码应该抽出来放进同一个函数中。
示例
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private Department _depart; |
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set { _name = value; } |
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public Department Depart |
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get { return _depart; } |
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set { _depart = value; } |
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public string DepartmentManager |
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get { return _depart.Manager; } |
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public class Department |
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private string _departName; |
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private User _manager; |
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public string DepartName |
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get { return _departName; } |
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set { _departName = value; } |
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get { return _manager; } |
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set { _manager = value; } |
改为
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private Department _depart; |
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set { _name = value; } |
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public Department Depart |
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get { return _depart; } |
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set { _depart = value; } |
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public class Department |
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private string _departName; |
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private User _manager; |
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public string DepartName |
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get { return _departName; } |
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set { _departName = value; } |
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get { return _manager; } |
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set { _manager = value; } |
在调用时就直接Depart.Manager来取得它的值.
