为什么当我添加ServiceStack OrmLite时，OrmLite会以空异常崩溃？

Question

我正在评估ServiceStack和OrmLite，并希望使用Firebird数据库进行尝试。使用ServiceStack.Northwind演示作为起点，当我将ServiceStack.OrmLite.Firebird引用添加到C#程序集引用时，应用程序在启动时开始崩溃，在程序集加载时出现空错误：

在Global.asax.cs中发生的代码行：

 public class AppHost : AppHostBase
    {
        public AppHost() : base("Northwind Web Services", typeof(CustomersService).Assembly) {}   // <-- Here!

例外情况：

System.TypeLoadException was unhandled by user code
  HResult=-2146233054
  Message=Method 'Execute' in type 'ServiceStack.Host.ServiceController' from assembly 'ServiceStack, Version=4.0.11.0, Culture=neutral, PublicKeyToken=null' does not have an implementation.
  Source=ServiceStack
  TypeName=ServiceStack.Host.ServiceController
  StackTrace:
       at ServiceStack.ServiceStackHost..ctor(String serviceName, Assembly[] assembliesWithServices)
       at ServiceStack.AppHostBase..ctor(String serviceName, Assembly[] assembliesWithServices)
       at ServiceStack.Northwind.AppHost..ctor() in C:\dev\ServiceStack.Examples\src\ServiceStack.Northwind\ServiceStack.Northwind\Global.asax.cs:line 13
       at ServiceStack.Northwind.Global.Application_Start(Object sender, EventArgs e) in C:\dev\ServiceStack.Examples\src\ServiceStack.Northwind\ServiceStack.Northwind\Global.asax.cs:line 31
  InnerException: 

演示源代码如下：https://github.com/ServiceStack/ServiceStack.Examples/tree/master/src/ServiceStack.Northwind (只需更改，就可以从包管理器控制台运行Install-Package ServiceStack.OrmLite.Firebird )。

下面是包管理器控制台会话：

Package Manager Console Host Version 3.1.1.0

Type 'get-help NuGet' to see all available NuGet commands.

PM> Install-Package ServiceStack.OrmLite.Firebird
Attempting to gather dependencies information for package 'ServiceStack.OrmLite.Firebird.4.0.44' with respect to project 'ServiceStack.Northwind', targeting '.NETFramework,Version=v4.0'
Attempting to resolve dependencies for package 'ServiceStack.OrmLite.Firebird.4.0.44' with DependencyBehavior 'Lowest'
Resolving actions to install package 'ServiceStack.OrmLite.Firebird.4.0.44'
Resolved actions to install package 'ServiceStack.OrmLite.Firebird.4.0.44'
Removed package 'ServiceStack.Common.4.0.11' from 'packages.config'
Successfully uninstalled 'ServiceStack.Common.4.0.11' from ServiceStack.Northwind
Removed package 'ServiceStack.Interfaces.4.0.11' from 'packages.config'
Successfully uninstalled 'ServiceStack.Interfaces.4.0.11' from ServiceStack.Northwind
Removed package 'ServiceStack.OrmLite.4.0.11' from 'packages.config'
Successfully uninstalled 'ServiceStack.OrmLite.4.0.11' from ServiceStack.Northwind
Removed package 'ServiceStack.Text.4.0.11' from 'packages.config'
Successfully uninstalled 'ServiceStack.Text.4.0.11' from ServiceStack.Northwind
Adding package 'FirebirdSql.Data.FirebirdClient.4.7.0' to folder 'C:\dev\ServiceStack.Examples\src\ServiceStack.Northwind\packages'
Added package 'FirebirdSql.Data.FirebirdClient.4.7.0' to folder 'C:\dev\ServiceStack.Examples\src\ServiceStack.Northwind\packages'
Added package 'FirebirdSql.Data.FirebirdClient.4.7.0' to 'packages.config'
Successfully installed 'FirebirdSql.Data.FirebirdClient 4.7.0' to ServiceStack.Northwind
Adding package 'ServiceStack.Interfaces.4.0.44' to folder 'C:\dev\ServiceStack.Examples\src\ServiceStack.Northwind\packages'
Added package 'ServiceStack.Interfaces.4.0.44' to folder 'C:\dev\ServiceStack.Examples\src\ServiceStack.Northwind\packages'
Added package 'ServiceStack.Interfaces.4.0.44' to 'packages.config'
Successfully installed 'ServiceStack.Interfaces 4.0.44' to ServiceStack.Northwind
Adding package 'ServiceStack.Text.4.0.44' to folder 'C:\dev\ServiceStack.Examples\src\ServiceStack.Northwind\packages'
Added package 'ServiceStack.Text.4.0.44' to folder 'C:\dev\ServiceStack.Examples\src\ServiceStack.Northwind\packages'
Added package 'ServiceStack.Text.4.0.44' to 'packages.config'
Successfully installed 'ServiceStack.Text 4.0.44' to ServiceStack.Northwind
Adding package 'ServiceStack.Common.4.0.44' to folder 'C:\dev\ServiceStack.Examples\src\ServiceStack.Northwind\packages'
Added package 'ServiceStack.Common.4.0.44' to folder 'C:\dev\ServiceStack.Examples\src\ServiceStack.Northwind\packages'
Added package 'ServiceStack.Common.4.0.44' to 'packages.config'
Successfully installed 'ServiceStack.Common 4.0.44' to ServiceStack.Northwind
Adding package 'ServiceStack.OrmLite.4.0.44' to folder 'C:\dev\ServiceStack.Examples\src\ServiceStack.Northwind\packages'
Added package 'ServiceStack.OrmLite.4.0.44' to folder 'C:\dev\ServiceStack.Examples\src\ServiceStack.Northwind\packages'
Added package 'ServiceStack.OrmLite.4.0.44' to 'packages.config'
Successfully installed 'ServiceStack.OrmLite 4.0.44' to ServiceStack.Northwind
Adding package 'ServiceStack.OrmLite.Firebird.4.0.44' to folder 'C:\dev\ServiceStack.Examples\src\ServiceStack.Northwind\packages'
Added package 'ServiceStack.OrmLite.Firebird.4.0.44' to folder 'C:\dev\ServiceStack.Examples\src\ServiceStack.Northwind\packages'
Added package 'ServiceStack.OrmLite.Firebird.4.0.44' to 'packages.config'
Successfully installed 'ServiceStack.OrmLite.Firebird 4.0.44' to ServiceStack.Northwind
PM> 

Answer 1

您不能将不同版本的ServiceStack库混合和匹配在一起。此错误表明，它仍在尝试加载ServiceStack的较旧版本4.0.11：

Message=Method 'Execute‘在程序集'ServiceStack，Version=4.0.11.0，Culture=neutral，PublicKeyToken=null’中键入'ServiceStack.Host.ServiceController‘没有实现。

我建议克隆ServiceStackApps/Northwind存储库，它只包含一个独立的复制Northwind项目，部署在northwind.servicestack.net Live网站上，它已经引用了最新的稳定版本4.0.44库，这将使修改变得更容易，而不会出现任何NuGet包升级问题。