步步为营 .NET 代码重构学习笔记八

叁歲伎倆 2021-12-23 00:53 250阅读 0赞

**一、Introduce Foreign Method（引入外加函数）**

**动机（Motivation）**

在client class 中建立一个函数，并以一个server class实体作为第一引数（argument）。

**示例**

DateTime newStart = DateTime.Now.AddDays(1);

改为

public DateTime  NextDate()
            {
                return  DateTime.Now.AddDays(1);
             
            }

**二、Introduce Local Extension（引入本地扩展）**

**动机（Motivation）**

建立一个新class，使它包含这些额外函数。让这个扩展品成为source class的subclass（子类）或wrapper（外覆类）。

**示例**

protected void Main()
            {
                Computer _computer;
                StringBuilder strCom = new StringBuilder();
                strCom.AppendLine("你的电脑配置如下:");
                strCom.AppendLine("主板是:" + _computer.MainBoard());
                strCom.AppendLine("处理器是:" + _computer.Cpu());
                strCom.AppendLine("显卡是:" + _computer.PhenoType());
                strCom.AppendLine("内存是:" + _computer.Memory());
                strCom.AppendLine("硬盘是:" + _computer.HardDisk());
                strCom.AppendLine("显示器是:" + _computer.Display());
                strCom.AppendLine("己组装完成");
                Console.WriteLine(strCom.ToString);
            }

改为

protected void Main()
            {
                Console.WriteLine(ShowComputerConfigure());
            }
    
            public string ShowComputerConfigure()
            {
                Computer _computer;
                StringBuilder strCom = new StringBuilder();
                strCom.AppendLine("你的电脑配置如下:");
                strCom.AppendLine("主板是:" + _computer.MainBoard());
                strCom.AppendLine("处理器是:" + _computer.Cpu());
                strCom.AppendLine("显卡是:" + _computer.PhenoType());
                strCom.AppendLine("内存是:" + _computer.Memory());
                strCom.AppendLine("硬盘是:" + _computer.HardDisk());
                strCom.AppendLine("显示器是:" + _computer.Display());
                strCom.AppendLine("己组装完成");
    
                return strCom.ToString();
            }

**三、Self Encapsulate Field（自封装值域）**

**动机（Motivation）**

为这个值域建立取值/设置函数（getting/setting methods），并且只以这些函数来访问值域。

**示例**

public  int _low, _high;
            public bool Includes(int arg)
            {
                return arg >= _low && arg <= _high;
            }

改为

private int _low, _high;
    
            public int Low
            {
                get { return _low; }
                set { _low = value; }
            }
    
            public int High
            {
                get { return _high; }
                set { _high = value; }
            }
    
            public bool Includes(int arg)
            {
                return arg >= Low && arg <= High;
            }

**四、Replace Data Value with Object（以对象取代数据值）**

**动机（Motivation）**

将数据项变成一个对象

**示例**

public class Customer
        {
            private string _name;
            public string Name
            {
                get { return _name; }
                set { _name = value; }
            }
        }

改为

public class Customer
        {
            private string _name;
            public string Name
            {
                get { return _name; }
                set { _name = value; }
            }
            public Customer(string name)
            {
                this._name = name;
            }
        }

引用时

string name = new Customer("spring yang");

**五、Change Value to Referencce（将实值对象改为引用对象）**

**动机（Motivation）**

将value object（实值对象）变成一个reference object（引用对象）

**示例**

public void GetCustomers()
            {
                string[] UserName = { new Customer("Spring Yang"), new Customer("Lemon Car"), new Customer("Associated Coffee") };
            }

改为

private Dictionary<string, Customer> dicUserName = new Dictionary<string, Customer>();
    
            public void GetCustomers()
            {
                string[] UserName = { dicUserName.TryGetValue("Spring Yang"), dicUserName.TryGetValue("Lemon Car"),
                                        dicUserName.TryGetValue("Associated Coffee") };
            }
    
            private void LoadCustomers()
            {
                AddCustomer("Spring Yang");
                AddCustomer("Lemon Car");
                AddCustomer("Associated Coffee");
            }
    
            private void AddCustomer(string name)
            {
                dicUserName.Add(name, new Customer(name));
            }

**六、Change Reference to Value（将引用对象改为实值对象）**

**动机（Motivation）**

reference object（引用对象），很小且不可变（immutable），而且不易管理。

**示例**

改为

public void GetCustomers()
            {
                string[] UserName = { new Customer("Spring Yang"), new Customer("Lemon Car"), new Customer("Associated Coffee") };
            }

**七、Replace Array with Object（以对象取代数组）**

**动机（Motivation）**

以对象替换数组。对于数组中的每个元素，以一个值域表示。

**示例**

public void Main()
            {
                string[] UserInfo = new string[3];
                UserInfo[0] = "1";
                UserInfo[1] = "spring yang";
                UserInfo[2] = "IT";
            }

改为

public void Main()
            {
                User user = new User();
                user.ID = "1";
                user.Name = "spring yang";
                user.Depart = "IT";
            }

转载于:https://www.cnblogs.com/springyangwc/archive/2011/05/30/2062474.html