Mono ASP.Net MVC EntityFramework异常

Question

I am trying to run my MVC application based on ASP.Net with the MVC 4 technology and the EntityFramework.

public ActionResult Test()
{
    DbEntities entities = new DbEntities();
    ViewBag.AddressBookList = entities.ADDRESSBOOK.Take(100).ToList();
    return View();
}

The problem is that I'm getting this exception when I'm calling /Home/Test. It must be caused by the EntityFramework because the whole application works except to the point when I'm trying to retrieve data of the database with the EntityFramework. When I test it within Visual Studio (IIS) it runs properly without any error.

System Informations

• Windows
• Net Framework 4.0
• ASP .Net MVC 4
• EntityFramework 6
• Mono 3.2.3 (newest Windows version)
• nginx FastCGI with fastcgi-mono-server4

System.UriFormatException

Invalid URI: The format of the URI could not be determined: System.Data.Resources.SqlClient.SqlProviderServices.ProviderManifest.xml

Stacktrace

at System.Uri..ctor (System.String uriString, Boolean dontEscape) [0x00000] in <filename unknown>:0
at System.Uri..ctor (System.String uriString) [0x00000] in <filename unknown>:0
at Mono.Xml.Schema.XmlSchemaValidatingReader..ctor (System.Xml.XmlReader reader, System.Xml.XmlReaderSettings settings) [0x00000] in <filename unknown>:0
at System.Xml.XmlReader.CreateValidatingXmlReader (System.Xml.XmlReader reader, System.Xml.XmlReaderSettings settings) [0x00000] in <filename unknown>:0
at System.Xml.XmlReader.CreateFilteredXmlReader (System.Xml.XmlReader reader, System.Xml.XmlReaderSettings settings) [0x00000] in <filename unknown>:0
at System.Xml.XmlReader.Create (System.Xml.XmlReader reader, System.Xml.XmlReaderSettings settings) [0x00000] in <filename unknown>:0
at System.Data.Entity.Core.SchemaObjectModel.Schema.Parse (System.Xml.XmlReader sourceReader, System.String sourceLocation) [0x00000] in <filename unknown>:0
at System.Data.Entity.Core.SchemaObjectModel.SchemaManager.ParseAndValidate (IEnumerable`1 xmlReaders, IEnumerable`1 sourceFilePaths, SchemaDataModelOption dataModel, System.Data.Entity.Core.SchemaObjectModel.AttributeValueNotification providerNotification, System.Data.Entity.Core.SchemaObjectModel.AttributeValueNotification providerManifestTokenNotification, System.Data.Entity.Core.SchemaObjectModel.ProviderManifestNeeded providerManifestNeeded, IList`1& schemaCollection) [0x00000] in <filename unknown>:0
at System.Data.Entity.Core.SchemaObjectModel.SchemaManager.ParseAndValidate (IEnumerable`1 xmlReaders, IEnumerable`1 sourceFilePaths, SchemaDataModelOption dataModel, System.Data.Entity.Core.Common.DbProviderManifest providerManifest, IList`1& schemaCollection) [0x00000] in <filename unknown>:0
at System.Data.Entity.Core.SchemaObjectModel.SchemaManager.LoadProviderManifest (System.Xml.XmlReader xmlReader, System.String location, Boolean checkForSystemNamespace, System.Data.Entity.Core.SchemaObjectModel.Schema& schema) [0x00000] in <filename unknown>:0
at System.Data.Entity.Core.Common.DbXmlEnabledProviderManifest.Load (System.Xml.XmlReader reader) [0x00000] in <filename unknown>:0
at System.Data.Entity.Core.Common.DbXmlEnabledProviderManifest..ctor (System.Xml.XmlReader reader) [0x00000] in <filename unknown>:0
at System.Data.Entity.SqlServer.SqlProviderManifest..ctor (System.String manifestToken) [0x00000] in <filename unknown>:0
at System.Data.Entity.SqlServer.SqlProviderServices.GetDbProviderManifest (System.String versionHint) [0x00000] in <filename unknown>:0
at System.Data.Entity.Core.Common.DbProviderServices.GetProviderManifest (System.String manifestToken) [0x00000] in <filename unknown>:0 

Answer 1

This issue is caused by Entity Framework generating invalid XML. For some reason, Microsoft's implementation of XmlReader doesn't follow the spec while Mono's does. Fortunately for most Mono users, the issue was patched in Mono nearly a year ago. You can view the pull request here:

https://github.com/mono/mono/pull/756

Unfortunately that doesn't help you since the latest version of Mono for Windows is over a year old. You can look at the issue in more depth at:

https://entityframework.codeplex.com/workitem/1632

Which may also help if you want to pull down the Entity Framework source and build from scratch with the patched code. If you can figure out the proper way, you may also be able to manually edit the offending XML so that it is valid and would no longer cause the Mono XML Reader to throw an Exception.

Of course, since you're already running on Windows, you could simply use IIS and avoid the issue completely.