建造者模式(Builder Pattern),也被称为生成器模式,是一种对象构建模式,旨在将复杂对象的构建过程与表示分离,使得同样的构建过程可以创建不同的表示。这种模式特别适用于构建具有多个组成部分的复杂对象,且这些组成部分的创建和组装方式相对独立。
cs
public class BuilderPatternTest
{
public void Main()
{
var director = new Director();//指挥者1
var director1 = new Director1();//指挥者2
var desktopBuilder = new DesktopBuilder();//建造者1
var desktopBuilder2 = new DesktopBuilder2();//建造者2
//第一台电脑,使用指挥者1,使用建造者1
var computer1 = director.Construct(desktopBuilder);
Console.WriteLine(computer1.ToString());
//第二台电脑,使用指挥者2,使用建造者2
var computer2 = director1.Construct(desktopBuilder);
Console.WriteLine(computer2.ToString());
//第三台电脑,使用指挥者1,使用建造者2
var computer3 = director.Construct(desktopBuilder2);
Console.WriteLine(computer3.ToString());
//第四台电脑,使用建造者1,不使用指挥者
var computer4 = new DesktopBuilder()
.SetType("平板电脑")
.SetRam(256)
.SetProcessor("i13212")
.Build();
Console.WriteLine(computer4.ToString());
}
}
// 定义产品类
public class Computer
{
public string Type { get; }
public bool IsGraphicsCardIncluded { get; }
public int Ram { get; }
public string Processor { get; }
public Computer(string type, bool isGraphicsCardIncluded, int ram, string processor)
{
Type = type;
IsGraphicsCardIncluded = isGraphicsCardIncluded;
Ram = ram;
Processor = processor;
}
public override string ToString()
{
return $"Type: {Type}, Graphics Card: {IsGraphicsCardIncluded}, RAM: {Ram}GB, Processor: {Processor}";
}
}
// 抽象建造者
// 也可以使用接口实现抽象建造者
// 方法中返回自身,以便链式调用
public abstract class Builder
{
protected string Type;
protected bool IsGraphicsCardIncluded;
protected int Ram;
protected string Processor;
public abstract Computer Build();
public virtual Builder SetType(string type)
{
return this;
}
public virtual Builder SetGraphicsCard(bool isGraphicsCardIncluded)
{
return this;
}
public virtual Builder SetRam(int ram)
{
return this;
}
public virtual Builder SetProcessor(string processor)
{
return this;
}
}
// 具体建造者
public class DesktopBuilder : Builder
{
public override Computer Build()
{
return new Computer(Type, IsGraphicsCardIncluded, Ram, Processor);
}
public override DesktopBuilder SetType(string type)
{
Type = type;
return this;
}
public override DesktopBuilder SetGraphicsCard(bool isGraphicsCardIncluded)
{
IsGraphicsCardIncluded = isGraphicsCardIncluded;
return this;
}
public override DesktopBuilder SetRam(int ram)
{
Ram = ram;
return this;
}
public override DesktopBuilder SetProcessor(string processor)
{
Processor = processor;
return this;
}
}
public class DesktopBuilder2 : Builder
{
public override Computer Build()
{
return new Computer(Type, IsGraphicsCardIncluded, Ram, Processor);
}
public override DesktopBuilder2 SetType(string type)
{
Type = type;
return this;
}
public override DesktopBuilder2 SetGraphicsCard(bool isGraphicsCardIncluded)
{
IsGraphicsCardIncluded = isGraphicsCardIncluded;
return this;
}
public override DesktopBuilder2 SetRam(int ram)
{
Ram = ram;
return this;
}
}
// 导演类
public class Director
{
public Computer Construct(Builder builder)
{
builder.SetType("台式电脑");
builder.SetGraphicsCard(true);
builder.SetRam(16);
builder.SetProcessor("i7");
return builder.Build();
}
}
public class Director1
{
public Computer Construct(Builder builder)
{
builder.SetType("笔记本电脑");
builder.SetGraphicsCard(true);
builder.SetRam(128);
builder.SetProcessor("i1000");
return builder.Build();
}
}