MVC模式下unity配置,报错“No connection string named '**Context' could be found in the application config file”

时间:2022-12-01 19:58:32

   写在前面: 第一次配置时好好的,后来第二次改到MVC模式,把依赖注入写成字典的单例模式时,由于新建的ORM(数据库映射模型EF),怎么弄都不用,一直报错"No connection string named '**Context' could be found in the application config file"(配置文件中找不到数据库context连接)调试了两小天问题,终于想到了是没有把EF模型中appconfig中的数据库连接复制到项目webconfig中导致的!!!改过之后果然好了,豁然开朗!

  中间也发现了一个小的点:调试的时候因为配置有问题,就改成不用配置直接写的方式:(如下)

            UnityContainer container = new UnityContainer();
container.RegisterType<DbContext, JDContext>();
container.RegisterType<IBaseService, BaseService>();
container.RegisterType<IUserMenuService, UserMenuService>(); IBaseService baseService = container.Resolve<IBaseService>();
IUserMenuService userservice = container.Resolve<IUserMenuService>();
JD_User a = userservice.Set<JD_User>().FirstOrDefault();

然后就报错BaseService是抽象类 不能实例化。 后来发现 这句不需要写出来
IBaseService baseService = container.Resolve<IBaseService>();

因为 IUserMenuService 继承了 IBaseService    实现IUserMenuService的时候自然就把基类带出来了实现了。

困惑了一天半 终于解决了。

以下是DI工厂实现

namespace Common
{
public class DIFactory
{
private static object _syncHelper = new object();
private static Dictionary<string, IUnityContainer> _UnityContainerDic = new Dictionary<string, IUnityContainer>(); public static IUnityContainer GetContainer(string containerName = "JDContainer")
{
if (!_UnityContainerDic.ContainsKey(containerName))
{
lock (_syncHelper)
{
if (!_UnityContainerDic.ContainsKey(containerName))
{
IUnityContainer container = new UnityContainer();
ExeConfigurationFileMap fileMap = new ExeConfigurationFileMap();
fileMap.ExeConfigFilename = Path.Combine(AppDomain.CurrentDomain.BaseDirectory + "CfgFiles\\Unity.Config.xml");
Configuration configuration = ConfigurationManager.OpenMappedExeConfiguration(fileMap, ConfigurationUserLevel.None);
UnityConfigurationSection section = (UnityConfigurationSection)configuration.GetSection(UnityConfigurationSection.SectionName);
section.Configure(container, containerName); _UnityContainerDic.Add(containerName, container);
}
}
}
return _UnityContainerDic[containerName];
}
}
}

以下是unity文件配置  (即上文代码中的 Unity.Config.xml )

<configuration>
<configSections>
<section name="unity" type="Microsoft.Practices.Unity.Configuration.UnityConfigurationSection, Microsoft.Practices.Unity.Configuration"/>
</configSections>
<unity>
<sectionExtension type="Microsoft.Practices.Unity.InterceptionExtension.Configuration.InterceptionConfigurationExtension, Microsoft.Practices.Unity.Interception.Configuration"/>
<containers>
<container name="JDContainer">
<!--<register type="Interface.ITest, Interface" mapTo="Service.Test, Service" />-->
<register type="System.Data.Entity.DbContext, EntityFramework" mapTo="EF.Model.JDContext, EF.Model"/>
<register type="Interface.IBaseService, Interface" mapTo="Service.BaseService, Service" />
<register type="Interface.IUserMenuService, Interface" mapTo="Service.UserMenuService, Service" />
</container>
<!--<container name="testContainer">
<register type="Interface.ITest, Interface" mapTo="Service.Test, Service" />
<register type="System.Data.Entity.DbContext, EntityFramework" mapTo="EF.yuncaidbEntities, EF"/>
<register type="Interface.IBaseService, Interface" mapTo="Service.BaseService, Service" />
<register type="Interface.IUserService, Interface" mapTo="Service.UserService, Service" />
</container>-->
</containers>
</unity>
</configuration>