C# 
public interface IBuilder<T> where T : class, new() 
{ 
T BuildUp(); 
} 

public class Builder<T> : IBuilder<T> where T : class, new() 
{ 
public virtual T BuildUp() 
{ 
IList<BuildStepAttribute> attributes = DiscoveryBuildSteps(); 
if (attributes == null) return new T(); // 没有BuildPart步骤，退化为Factory模式 
T target = new T(); 
foreach (BuildStepAttribute attribute in attributes) 
for (int i = 0; i < attribute.Times; i++) 
attribute.Handler.Invoke(target, null); 
return target; 
} 

/// 借助反射获得类型T 所需执行BuildPart()的自动发现机制 
protected virtual IList<BuildStepAttribute> DiscoveryBuildSteps() 
{ 
IList<MethodInfo> methods = 
AttributeHelper.GetMethodsWithCustomAttribute<BuildStepAttribute>(typeof(T)); 
if ((methods == null) || (methods.Count == 0)) return null; 
BuildStepAttribute[] attributes = new BuildStepAttribute[methods.Count]; 
for (int i = 0; i < methods.Count; i++) 
{ 
BuildStepAttribute attribute = 
AttributeHelper.GetMethodCustomAttribute<BuildStepAttribute>(methods[i]); 
attribute.Handler = methods[i]; 
attributes[i] = attribute; 
} 
Array.Sort<BuildStepAttribute>(attributes); 
return new List<BuildStepAttribute>(attributes); 
} 
} 
Unit Test 
[TestClass] 
public class TestBuilder 
{ 
public class Car 
{ 
public IList<string> Log = new List<string>(); 
[BuildStep(2)] 
public void AddWheel() { Log.Add("wheel"); } 
public void AddEngine() { Log.Add("engine"); } 
[BuildStep(1, 2)] 
public void AddBody() { Log.Add("body"); } 
} 

[TestMethod] 
public void Test() 
{ 
Builder<Car> builder = new Builder<Car>(); 
Car car = builder.BuildUp(); 
Assert.IsNotNull(car); 
Assert.AreEqual<int>(2 + 1, car.Log.Count); // 实际只执行了两个方法, 但3次调用 
Assert.AreEqual<string>("body", car.Log[0]); // 按照标注的次序执行 
Assert.AreEqual<string>("wheel", car.Log[2]); // 按照标注的次序执行 
} 
}