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
01 |
public class Person
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02 |
{ |
03 |
private string _name;
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private string _officeAreaCode;
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05 |
private string _officeNumber;
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06 |
07 |
public string Name
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{
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get { return _name; }
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10 |
set { _name = value; }
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11 |
}
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12 |
13 |
public string OfficeAreaCode
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{
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get { return _officeAreaCode; }
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set { _officeAreaCode = value; }
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}
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18 |
19 |
public string OfficeNumber
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{
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get { return _officeNumber; }
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set { _officeNumber = value; }
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}
|
24 |
25 |
public string TelephoneNumber
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{
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get { return "(" + _officeAreaCode + ")" + _officeNumber; }
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}
|
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} |
改为
01 |
public class Person
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{
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03 |
private string _name;
|
04 |
private Telephone _telephoneNumber;
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05 |
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public Telephone TelephoneNumber
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{
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get { return _telephoneNumber; }
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set { _telephoneNumber = value; }
|
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}
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11 |
12 |
public string Name
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{
|
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get { return _name; }
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set { _name = value; }
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}
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17 |
18 |
public string TemphoneNumber
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{
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get { return _telephoneNumber.TelephoneNumber; }
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}
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22 |
23 |
}
|
24 |
public class Telephone
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{
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private string _officeAreaCode;
|
27 |
private string _officeNumber;
|
28 |
public string OfficeAreaCode
|
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{
|
30 |
get { return _officeAreaCode; }
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set { _officeAreaCode = value; }
|
32 |
}
|
33 |
34 |
public string OfficeNumber
|
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{
|
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get { return _officeNumber; }
|
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set { _officeNumber = value; }
|
38 |
}
|
39 |
40 |
public string TelephoneNumber
|
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{
|
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get { return "(" + _officeAreaCode + ")" + _officeNumber; }
|
43 |
}
|
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}
|
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
01 |
public class User
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02 |
{ |
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private int _ID;
|
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private string _name;
|
05 |
06 |
public int ID
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{
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get { return _ID; }
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set { _ID = value; }
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10 |
}
|
11 |
12 |
public string Name
|
13 |
{
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get { return _name; }
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set { _name = value; }
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}
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17 |
18 |
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} |
20 |
public class UserInfo
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{ |
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private int _ID;
|
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private string _Age;
|
24 |
25 |
public string ID
|
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{
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get { return _ID; }
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set { _ID = value; }
|
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}
|
30 |
31 |
public string Age
|
32 |
{
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get { return _Age; }
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set { _Age = value; }
|
35 |
}
|
36 |
} |
改为
01 |
public class User
|
02 |
{ |
03 |
private int _ID;
|
04 |
private string _name;
|
05 |
private string _Age;
|
06 |
07 |
public int ID
|
08 |
{
|
09 |
get { return _ID; }
|
10 |
set { _ID = value; }
|
11 |
}
|
12 |
13 |
public string Name
|
14 |
{
|
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get { return _name; }
|
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set { _name = value; }
|
17 |
}
|
18 |
19 |
public string Age
|
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{
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get { return _Age; }
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set { _Age = value; }
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23 |
}
|
24 |
} |
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
01 |
public class User
|
02 |
{ |
03 |
private int _ID;
|
04 |
private string _name;
|
05 |
private Department _depart;
|
06 |
07 |
public int ID
|
08 |
{
|
09 |
get { return _ID; }
|
10 |
set { _ID = value; }
|
11 |
}
|
12 |
13 |
public string Name
|
14 |
{
|
15 |
get { return _name; }
|
16 |
set { _name = value; }
|
17 |
}
|
18 |
19 |
public Department Depart
|
20 |
{
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get { return _depart; }
|
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set { _depart = value; }
|
23 |
}
|
24 |
25 |
} |
26 |
27 |
public class Department
|
28 |
{ |
29 |
private string _departName;
|
30 |
private User _manager;
|
31 |
32 |
public string DepartName
|
33 |
{
|
34 |
get { return _departName; }
|
35 |
set { _departName = value; }
|
36 |
}
|
37 |
38 |
public User Manager
|
39 |
{
|
40 |
get { return _manager; }
|
41 |
set { _manager = value; }
|
42 |
}
|
43 |
} |
改为
01 |
public class User
|
02 |
{
|
03 |
private int _ID;
|
04 |
private string _name;
|
05 |
private Department _depart;
|
06 |
07 |
public int ID
|
08 |
{
|
09 |
get { return _ID; }
|
10 |
set { _ID = value; }
|
11 |
}
|
12 |
13 |
public string Name
|
14 |
{
|
15 |
get { return _name; }
|
16 |
set { _name = value; }
|
17 |
}
|
18 |
19 |
public Department Depart
|
20 |
{
|
21 |
get { return _depart; }
|
22 |
set { _depart = value; }
|
23 |
}
|
24 |
25 |
public string DepartmentManager
|
26 |
{
|
27 |
get { return _depart.Manager; }
|
28 |
}
|
29 |
}
|
30 |
31 |
public class Department
|
32 |
{
|
33 |
private string _departName;
|
34 |
private User _manager;
|
35 |
36 |
public string DepartName
|
37 |
{
|
38 |
get { return _departName; }
|
39 |
set { _departName = value; }
|
40 |
}
|
41 |
42 |
public User Manager
|
43 |
{
|
44 |
get { return _manager; }
|
45 |
set { _manager = value; }
|
46 |
}
|
47 |
}
|
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
01 |
public class User
|
02 |
{ |
03 |
private int _ID;
|
04 |
private string _name;
|
05 |
private Department _depart;
|
06 |
07 |
public int ID
|
08 |
{
|
09 |
get { return _ID; }
|
10 |
set { _ID = value; }
|
11 |
}
|
12 |
13 |
public string Name
|
14 |
{
|
15 |
get { return _name; }
|
16 |
set { _name = value; }
|
17 |
}
|
18 |
19 |
public Department Depart
|
20 |
{
|
21 |
get { return _depart; }
|
22 |
set { _depart = value; }
|
23 |
}
|
24 |
25 |
public string DepartmentManager
|
26 |
{
|
27 |
get { return _depart.Manager; }
|
28 |
}
|
29 |
} |
30 |
31 |
public class Department
|
32 |
{ |
33 |
private string _departName;
|
34 |
private User _manager;
|
35 |
36 |
public string DepartName
|
37 |
{
|
38 |
get { return _departName; }
|
39 |
set { _departName = value; }
|
40 |
}
|
41 |
42 |
public User Manager
|
43 |
{
|
44 |
get { return _manager; }
|
45 |
set { _manager = value; }
|
46 |
}
|
47 |
} |
改为
01 |
public class User
|
02 |
{ |
03 |
private int _ID;
|
04 |
private string _name;
|
05 |
private Department _depart;
|
06 |
07 |
public int ID
|
08 |
{
|
09 |
get { return _ID; }
|
10 |
set { _ID = value; }
|
11 |
}
|
12 |
13 |
public string Name
|
14 |
{
|
15 |
get { return _name; }
|
16 |
set { _name = value; }
|
17 |
}
|
18 |
19 |
public Department Depart
|
20 |
{
|
21 |
get { return _depart; }
|
22 |
set { _depart = value; }
|
23 |
}
|
24 |
25 |
} |
26 |
27 |
public class Department
|
28 |
{ |
29 |
private string _departName;
|
30 |
private User _manager;
|
31 |
32 |
public string DepartName
|
33 |
{
|
34 |
get { return _departName; }
|
35 |
set { _departName = value; }
|
36 |
}
|
37 |
38 |
public User Manager
|
39 |
{
|
40 |
get { return _manager; }
|
41 |
set { _manager = value; }
|
42 |
}
|
43 |
} |
在调用时就直接Depart.Manager来取得它的值.
