C# 如何实现一个工厂模式_C# 工厂模式实现方法详解

// 产品接口
public interface IProduct
{
    void Use();
}
<p>// 具体产品A
public class ConcreteProductA : IProduct
{
public void Use() => Console.WriteLine("使用产品A");
}</p><p>// 具体产品B
public class ConcreteProductB : IProduct
{
public void Use() => Console.WriteLine("使用产品B");
}</p><p>// 简单工厂
public class SimpleFactory
{
public static IProduct CreateProduct(string type)
{
return type.ToUpper() switch
{
"A" => new ConcreteProductA(),
"B" => new ConcreteProductB(),
_ => throw new ArgumentException("无效的产品类型")
};
}
}</p>

IProduct product = SimpleFactory.CreateProduct("A");
product.Use(); // 输出：使用产品A

// 抽象工厂
public abstract class Factory
{
    public abstract IProduct CreateProduct();
}
<p>// 具体工厂A
public class ConcreteFactoryA : Factory
{
public override IProduct CreateProduct() => new ConcreteProductA();
}</p><p>// 具体工厂B
public class ConcreteFactoryB : Factory
{
public override IProduct CreateProduct() => new ConcreteProductB();
}</p>

Factory factory = new ConcreteFactoryA();
IProduct product = factory.CreateProduct();
product.Use(); // 输出：使用产品A

// 抽象产品：按钮
public interface IButton
{
    void Render();
}
<p>// 具体产品：Windows 按钮
public class WindowsButton : IButton
{
public void Render() => Console.WriteLine("渲染 Windows 风格按钮");
}</p><p>// 具体产品：Mac 按钮
public class MacButton : IButton
{
public void Render() => Console.WriteLine("渲染 Mac 风格按钮");
}</p><p>// 抽象工厂
public interface IGuiFactory
{
IButton CreateButton();
}</p><p>// 具体工厂：Windows 工厂
public class WindowsFactory : IGuiFactory
{
public IButton CreateButton() => new WindowsButton();
}</p><p>// 具体工厂：Mac 工厂
public class MacFactory : IGuiFactory
{
public IButton CreateButton() => new MacButton();
}</p>

IGuiFactory factory = new MacFactory(); // 或 new WindowsFactory()
IButton button = factory.CreateButton();
button.Render(); // 输出：渲染 Mac 风格按钮