Question

我正在尝试将AutoMapper与在IIS 7上运行的Web应用程序一起使用。目的是使用它来映射外部dll中定义的域类型，以查看IIS应用程序中定义的模型。这种方法很好，除非外部dll烧焦。然后我收到以下错误：

AutoMapper.AutoMapperMappingException was unhandled by user code
  Message="Trying to map TestLibrary.Source to WebApplication1.Destination.\nUsing mapping configuration for TestLibrary.Source to WebApplication1.Destination\nException of type 'AutoMapper.AutoMapperMappingException' was thrown."
  Source="AutoMapper"
  StackTrace:
       at AutoMapper.MappingEngine.AutoMapper.IMappingEngineRunner.Map(ResolutionContext context)
       at AutoMapper.MappingEngine.Map(Object source, Type sourceType, Type destinationType)
       at AutoMapper.MappingEngine.Map[TSource,TDestination](TSource source)
       at AutoMapper.Mapper.Map[TSource,TDestination](TSource source)
       at WebApplication1._Default.Page_Load(Object sender, EventArgs e)
       at System.Web.Util.CalliHelper.EventArgFunctionCaller(IntPtr fp, Object o, Object t, EventArgs e)
       at System.Web.Util.CalliEventHandlerDelegateProxy.Callback(Object sender, EventArgs e)
       at System.Web.UI.Control.OnLoad(EventArgs e)
       at System.Web.UI.Control.LoadRecursive()
       at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)
  InnerException: AutoMapper.AutoMapperMappingException
       Message="Trying to map TestLibrary.Source to System.Object.\nUsing mapping configuration for TestLibrary.Source to WebApplication1.Destination\nDestination property: Value\nException of type 'AutoMapper.AutoMapperMappingException' was thrown."
       Source="AutoMapper"
       StackTrace:
            at AutoMapper.Mappers.TypeMapObjectMapperRegistry.PropertyMapMappingStrategy.MapPropertyValue(ResolutionContext context, IMappingEngineRunner mapper, Object mappedObject, PropertyMap propertyMap)
            at AutoMapper.Mappers.TypeMapObjectMapperRegistry.PropertyMapMappingStrategy.Map(ResolutionContext context, IMappingEngineRunner mapper)
            at AutoMapper.Mappers.TypeMapMapper.Map(ResolutionContext context, IMappingEngineRunner mapper)
            at AutoMapper.MappingEngine.AutoMapper.IMappingEngineRunner.Map(ResolutionContext context)
       InnerException: System.Security.SecurityException
            Message="Request failed."
            Source="Anonymously Hosted DynamicMethods Assembly"
            StackTrace:
                 at lambda_method(ExecutionScope , Object )
                 at AutoMapper.Internal.PropertyGetter.GetValue(Object source)
                 at AutoMapper.Internal.MemberGetter.Resolve(ResolutionResult source)
                 at AutoMapper.PropertyMap.ResolveValue(Object input)
                 at AutoMapper.Mappers.TypeMapObjectMapperRegistry.PropertyMapMappingStrategy.MapPropertyValue(ResolutionContext context, IMappingEngineRunner mapper, Object mappedObject, PropertyMap propertyMap)
            InnerException:

重现问题的步骤：

1）在安装了IIS 7的计算机上使用Visual Studio 2008创建新的Web应用程序。（我们正在使用Windows 7）。

2）从http://www.codeplex.com/AutoMapper下载AutoMapper.dll。（我们使用的是版本0.4.x.x）并在您的Web应用程序中添加对此Dll的引用。

3）将以下代码放在默认页面的代码中：

using System;
using AutoMapper;
using TestLibrary;

namespace WebApplication1
{
    public partial class _Default : System.Web.UI.Page
    {
        protected void Page_Load(object sender, EventArgs e)
        {
            Mapper.CreateMap<Source, Destination>();
            Mapper.AssertConfigurationIsValid();

            var source = new Source {Value = "Automapper works!" };
            var destination = Mapper.Map<Source, Destination>(source);

            Response.Clear();
            Response.ContentType="text/plain";
            Response.Write(destination.Value);
            Response.End();
        }
    }

    public class Destination
    {
        public object Value { get; set; }
    }

4）创建一个名为“TestLibrary”的新类库，并将Class1.cs文件重命名为Source.cs，并将以下代码放入其中：

namespace TestLibrary
{
    public class Source
    {
        public object Value { get; set; }
    }
}

5）将此库的引用添加到Web应用程序中。

6）运行解决方案，您应该看到“Automapper工作！”输出

7）要使它失败，你必须做两件事 i）将网站配置为在IIS下运行，而不是在Visual Studio开发服务器上运行。 ii）签署TestLibrary程序集。之后，运行解决方案应该会产生上面报告的错误。

有没有人知道怎么解决这个问题？我们已经检查过，并且应用程序正在以完全信任的方式运行IIS管理控制台。

Answer 1

因此，此异常来自以编程方式创建lambda表达式然后编译它。你可以尝试在Default.aspx.cs中做同样的事情吗？一种方法是在代码中创建一个lambda表达式：

表达式＆GT; expr =（）=＆gt; 5;

然后做：

var func = expr.Compile（）;

这就像你失败的那条线。

如果这样可行，我接下来会将此代码放入已签名的程序集中，并从Web应用程序访问它。

使用签名程序集时IIS7中的AutoMapper出现问题

1 个答案: