未处理typeinitializationexception。'System.Data.Entity.Internal.AppConfig'的类型初始值设定项引发了异常

Question

I have created a Entity Framework DLL EMPDAL which points to Employees Table of Northwnd database. Below is the code for Entity framework

namespace EmpDAL{
public class EmplooyeeData
{
    public static List<Employee> GetEmployees( int EmployeeId)
    {
        using (DbEntities dbContext = new DbEntities())
        {
            return dbContext.Employees.Where(x => x.EmployeeID == EmployeeId).ToList();
        }
    }
    public static void SaveEmployee(Employee emp)
    {
        DbEntities dbContext = new DbEntities();
        dbContext.Employees.Add(emp);
        dbContext.SaveChanges();
    }
}}

Below is the Appconfig file of EMPDAL

<configuration>
  <configSections>
    <!-- For more information on Entity Framework configuration, visit http://go.microsoft.com/fwlink/?LinkID=237468 -->
    <section name="entityFramework" type="System.Data.Entity.Internal.ConfigFile.EntityFrameworkSection, EntityFramework, Version=6.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" requirePermission="false" />
  </configSections>
  <connectionStrings>
    <add name="DbEntities" connectionString="metadata=res://*/EmployeeModel.csdl|res://*/EmployeeModel.ssdl|res://*/EmployeeModel.msl;provider=System.Data.SqlClient;provider connection string=&quot;data source=localhost;initial catalog=NorthWnd;user id=sa;MultipleActiveResultSets=True;App=EntityFramework&quot;" providerName="System.Data.EntityClient" />
  </connectionStrings>
  <entityFramework>
    <defaultConnectionFactory type="System.Data.Entity.Infrastructure.SqlConnectionFactory, EntityFramework" />
  </entityFramework>
</configuration>

Below is the code for the WCF service

namespace EmployeeService{

public class EmployeeService : IEmployeeService
{
    public List<EmpDAL.Employee> GetEmployees(int Empid)
    {
        return EmpDAL.EmplooyeeData.GetEmployees(Empid);
    }

    public void SaveChanges(EmpDAL.Employee emp)
    {
        EmpDAL.EmplooyeeData.SaveEmployee(emp);
    }
}}

Below is the AppConfig for WCF EmployeeService

 <configuration>
<system.serviceModel>
    <behaviors>
        <serviceBehaviors>
            <behavior name="">
                <serviceMetadata httpGetEnabled="true" httpsGetEnabled="true" />
                <serviceDebug includeExceptionDetailInFaults="false" />
            </behavior>
        </serviceBehaviors>
    </behaviors>
    <services>
        <service name="EmployeeService.EmployeeService">
            <endpoint address="" binding="basicHttpBinding" contract="EmployeeService.IEmployeeService">
                <identity>
                    <dns value="localhost" />
                </identity>
            </endpoint>
            <endpoint address="mex" binding="mexHttpBinding" contract="IMetadataExchange" />
            <host>
                <baseAddresses>
                    <add baseAddress="http://localhost:8733/Design_Time_Addresses/EmployeeService/EmployeeService/" />
                </baseAddresses>
            </host>
        </service>
    </services>
</system.serviceModel>  <configSections>
    <section name="entityFramework" type="System.Data.Entity.Internal.ConfigFile.EntityFrameworkSection, EntityFramework, Version=6.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" requirePermission="false" />  </configSections>  <connectionStrings>
<add name="DbEntities"connectionString="metadata=res://*/EmployeeModel.csdl|res://*/EmployeeModel.ssdl|res://*/EmployeeModel.msl;provider=System.Data.SqlClient;provider connection string=&quot;data source=localhost;initial catalog=NorthWnd;user id=sa;MultipleActiveResultSets=True;App=EntityFramework&quot;" providerName="System.Data.EntityClient" /></connectionStrings>  <entityFramework>   <defaultConnectionFactory type="System.Data.Entity.Infrastructure.SqlConnectionFactory,EntityFramework" /> </entityFramework></configuration>

When client uses the WCF service it and when it tries to execute "using (DbEntities dbContext = new DbEntities())" it goes to

 public partial class DbEntities : DbContext    {
    public DbEntities()
        : base("name=DbEntities")

and throws exception

typeinitializationexception was unhandled .The type initializer for 'System.Data.Entity.Internal.AppConfig' threw an exception.

Answer 1

It is very generic exception so in your editor try reading the whole details of the exception and then resolve it. For me, it was due to the entity framework version written in webconfig file and actual file included ,there was difference and also i had to remove providers tag in web config file of my project