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Unity Container 应用示例

一项目引用Unity

右键项目引用-> 管理Nuget包->搜索unity->安装Unity 和 Unity Interception Extension,如下图所示.

二创建基础类

我们以商品查询的数据层注入为例.

1.首先创建商品实体Model. 如果商品信息要被序列化,就要为该类添加Serializable特性.

public class Product {  public int Id { get; set; }  public string Name { get; set; }  public int Price { get; set; }  public override string ToString()  {   return string.Format(" Product id:{0}/r/n Name:{1}/r/n Price:{2}/r/n",Id,Name,Price);  } }

2.创建数据层接口及其实现类.

public interface IProductDao     {         Product Get(int id);     }

public class ProductDao:IProductDao {  public Product Get(int id)  {   #warning product info for test   return new Product()   {    Id = id,    Name = "Product"+id,    Price = id*10   };  } }

3.直接创建实例

其实有了以上内容就可以调用查询商品信息了.

static void Main( string[] args)   {  IProductDao productDao= new ProductDao();  Product product = productDao.Get(5);  Console.WriteLine(product.ToString());  Console.Read();   }

Unity Container 应用示例

不过在项目中使用这种方式的话,耦合度比较高.一旦想修改IProductDao的实现方式涉及到的地方就太多了. 使用Unity实现依赖注入可以降低耦合.

三.使用Unity实现依赖注入

1.创建Unity配置文件

<? xml version= "1.0 "?>  < configuration>    < configSections>      <!-- unity程序集-->      < section name= "unity " type =" Microsoft.Practices.Unity.Configuration.UnityConfigurationSection, Microsoft.Practices.Unity.Configuration" />    </ configSections>    < unity xmlns= "http://schemas.microsoft.com/practices/2010/unity ">      <!-- 程序集和命名空间 -->      < assembly name= "DemoCache "/>      < namespace name= "DemoCache.Dao "/>      < namespace name= "DemoCache.Dao.Impl "/>      < container name= "Dao ">        <!-- 商品 -->        < register type= "IProductDao " mapTo= "ProductDao "></ register>      </ container>    </ unity>  </ configuration>

2.创建UnityContainerManager类

创建UnityContainerManager读取Unity.config配置. 完整代码见附件,重点看一下从Unity.config读取配置信息的方法:

private IUnityContainer LoadUnityConfig() {  ////根据文件名获取指定config文件  string filePath = AppDomain.CurrentDomain.BaseDirectory + @"Configs/Unity.config";  var fileMap = new ExeConfigurationFileMap { ExeConfigFilename = filePath };  //从config文件中读取配置信息  Configuration configuration = ConfigurationManager.OpenMappedExeConfiguration(fileMap, ConfigurationUserLevel.None);  var unitySection = (UnityConfigurationSection)configuration.GetSection("unity");  var container = new UnityContainer();  foreach (var item in unitySection.Containers)  {   container.LoadConfiguration(unitySection, item.Name);  }  return container; }

3.调用示例

static void Main( string[] args)   {  IProductDao productDao = UnityContainerManager .Instance.Resolve<IProductDao >();  Product product = productDao.Get(8);  Console.WriteLine(product.ToString());  Console.Read();   }

四使用Unity Interception实现日志

1.创建ICallHandler接口实现类

新建类LogCallHandler类,实现接口ICallHandler. 每次调用相应方法时会自动将执行时间写入日志.

public class LogCallHandler:ICallHandler  {   public IMethodReturn Invoke(IMethodInvocation input, GetNextHandlerDelegate getNext)   {    //计时开始    var stopWatch = new Stopwatch();    stopWatch.Start();    //执行方法    IMethodReturn result = getNext()(input, getNext);    //计时结束    stopWatch.Stop();    //记录日志    var argumentsSb = new StringBuilder(input.MethodBase.Name);    for (var i = 0; i < input.Arguments.Count; i++)    {     argumentsSb.AppendFormat("-{0}:{1}", input.Arguments.ParameterName(i), input.Arguments[i]);    }    LogHelper.LogInfo(string.Format("{2} 方法 {0},执行时间 {1} ms", argumentsSb, stopWatch.ElapsedMilliseconds,Msg));    return result;   }   public int Order { get; set; }   public string Msg { get; set; }  }

2.创建特性

创建特性LogTime,它需要实现HandlerAttribute.

public class LogTimeAttributes:HandlerAttribute {  public int Order { get; set; }  public string Msg { get; set; }  public override ICallHandler CreateHandler(IUnityContainer container)  {   return new LogCallHandler()   {    Order = Order,    Msg = Msg   };  } }

3.使用特性

[LogTimeAttributes (Order = 1,Msg = "查询单个商品信息" )]

4.配置Unity.config

配置Unity Interception需要在unity节点下添加:

< sectionExtension

type =" Microsoft.Practices.Unity.InterceptionExtension.Configuration.InterceptionConfigurationExtension,Microsoft.Practices.Unity.Interception.Configuration ">

</ sectionExtension >

然后在container节点下添加:

< extension type= "Interception " />

最后调整IProductDao的注册节点:

< register type= "IProductDao " mapTo= "ProductDao ">          < interceptor type =" InterfaceInterceptor" />          < policyInjection />  </ register>

调用处不用做调整,结果如下:

Unity Container 应用示例

5.不使用Unity.config配置文件

其实如果不走Unity.config配置文件,也可以直接在代码中设置.

static void Main(string[] args) {    var container = new UnityContainer().AddNewExtension<Interception>().RegisterType<IProductDao, ProductDao>();  container.Configure<Interception>().SetInterceptorFor<IProductDao>(new InterfaceInterceptor());  IProductDao productDao = container.Resolve<IProductDao>();  Product product = productDao.Get(8);  Console.WriteLine(product);  Console.Read(); }

代码: http://files.cnblogs.com/files/janes/DemoCache.zip

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