4

为了说明问题，这是我的设置的简化版本。我有一个像这样的工厂：

public interface IFactory{ }

public class Factory : IFactory
{
    public Factory()
    {
        Console.WriteLine("parameterless");
    }

    //public Factory(int i)
    //{
    //    Console.WriteLine("with parameter : {0}", i);
    //}

}

测试这个的程序是一个consoleApp。足以证明我的观点。

static void Main(string[] args)
{
     Init();
     var factory1 = ObjectFactory.GetInstance<IFactory>();
     var factory2 = ObjectFactory.GetInstance<IFactory>();
     var factory3 = ObjectFactory.GetInstance<IFactory>();
     Console.Read();
 }

我在我的 Init 静态方法中设置了 strucutreMap。 

  public static void Init()
        {
            ObjectFactory.Initialize(x =>
            {
                 //insert Initialization code here.
            });
        }

如果我只有一个构造函数并像这样设置 StructureMap ：

x.For<IFactory>().Use<Factory>();

效果很好，输出显示无
参数无
参数无
参数

每个调用都会构建一个新实例。

现在，如果我取消注释第二个构造函数，但我想使用无参数的构造函数，并且具有相同的默认生活方式。我该怎么办？

我试过了：

x.SelectConstructor<IFactory>(() => new Factory());
x.For<IFactory>().Use<Factory>();

它只是不起作用：InstanceKey 缺少请求的实例属性“i”

如果我喜欢这样：

 x.For<IFactory>().Use(new Factory());

It works, but the output is just one "parameterless" meaning it's not building a new instance for each call. It's using this specific instance I pass in.

The only way I found is to add the [DefaultConstructor] on top of my parameterless constructor and use the standard x.For().Use(); But I don't want to add this attribute and spread the configuration accross my model.

Help?

4

1 回答 1

9

SelectConstructor takes the concrete type, not the interface. Of course, an interface doesnt have any constructor. But nothing breaks, it's just ignored.... so I couldnt spot that error.

 x.SelectConstructor<IFactory>(() => new Factory());
 x.For<IFactory>().Use<Factory>();

should be 

 x.SelectConstructor<**Factory**>(() => new Factory());
 x.For<IFactory>().Use<Factory>();
于 2010-02-24T14:12:21.233 回答