BiffBaffBoff BiffBaffBoff - 2 months ago 32
C# Question

The context cannot be used while the model is being created

In my application I receive the following error:


The context cannot be used while the model is being created.


I'm not sure what this means. I have done everything as normal and usually it works but for this one it isnt. Below is my code:

App.config:

<connectionStrings>
<add name="DatabaseContext" connectionString="Data Source=./SQLEXPRESS;Initial Catalog=ProjectCode;Integrated Security=SSPI;" providerName="System.Data.SqlClient" />
</connectionStrings>


Products.cs:

class Products
{
public int ProductID { get; set; }
public string ProductName { get; set; }
}


DatabaseContext.cs:

class DatabaseContext : DbContext
{
public DbSet<Products> Products { get; set; }
}


Program.cs:

DatabaseContext context = new DatabaseContext();

try
{
var products = context.Products.ToList();

foreach (var item in products)
{
Console.WriteLine(item.ProductID + " : " + item.ProductName);
}
Console.ReadLine();
}


The line is fails on is
var products = context.Products.ToList();


Any ideas what could be causing this? I have set up 2 products in my database so it should be outputting them.

EDIT



Here is my whole App.config file:

<?xml version="1.0" encoding="utf-8"?>
<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=4.3.1.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" />
</configSections>
<connectionStrings>
<add name="DatabaseContext" connectionString="Data Source=./SQLEXPRESS;Initial Catalog=ProjectCode;Integrated Security=SSPI;MultipleActiveResultSets=true" providerName="System.Data.SqlClient" />
</connectionStrings>
<startup>
<supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.5" />
</startup>
<entityFramework>
<defaultConnectionFactory type="System.Data.Entity.Infrastructure.SqlConnectionFactory, EntityFramework">
<parameters>
<parameter value="Data Source=.\SQLEXPRESS; Integrated Security=True; MultipleActiveResultSets=True" />
</parameters>
</defaultConnectionFactory>
</entityFramework>
</configuration>

Answer

In your App.Config file under connectionstrings you had a forward slash (./SQLEXPRESS). Change this to a backslash .\SQLEXPRESS like so:

<add name="DatabaseContext" connectionString="Data Source=.\SQLEXPRESS;Initial Catalog=ProjectCode;Integrated Security=SSPI;" providerName="System.Data.SqlClient" />