Having trouble compiling code-first EF4 class in runtime

Question

I'm try to compile this code at run time. this code is a code-first EF4 class.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.ComponentModel.DataAnnotations;

namespace EFCodeFirst.Model.Models
{
    [Table("Blog")]
    public class Blog
    {
        public Guid Id { get; set; }
        [Column("txtTitle")]
        public string Title { get; set; }
        [DatabaseGenerated(DatabaseGeneratedOption.None)]
        public string ShortTitle { get { return Title; } }
        public string BloggerName { get; set; }
        public virtual ICollection<Post> Posts { get; set; }
    }

    public class Post
    {
        public Guid Id { get; set; }
        public string Title { get; set; }
        public DateTime DateCreated { get; set; }
        public string Content { get; set; }
        public Guid BlogId { get; set; }
    }
}

using this method that compile the given code. I tested this code with a simple class. it works. but with given class, it doesn't work at all.

private Assembly BuildAssembly(string code)
        {
            Microsoft.CSharp.CSharpCodeProvider provider = new CSharpCodeProvider();
            ICodeCompiler compiler = provider.CreateCompiler();
            CompilerParameters compilerparams = new CompilerParameters();
	    compilerparams.ReferencedAssemblies.Add("mscorlib.dll"); 
            compilerparams.ReferencedAssemblies.Add("System.dll");
            compilerparams.ReferencedAssemblies.Add("System.Core.dll"); 
            compilerparams.ReferencedAssemblies.Add("System.Xml.dll");
            compilerparams.ReferencedAssemblies.Add("System.ComponentModel.DataAnnotations.dll");


            compilerparams.GenerateExecutable = false;
            compilerparams.GenerateInMemory = true;
            CompilerResults results = compiler.CompileAssemblyFromSource(compilerparams, code);
            if (results.Errors.HasErrors)
            {
                StringBuilder errors = new StringBuilder("Compiler Errors :\r\n");
                foreach (CompilerError error in results.Errors)
                {
                    errors.AppendFormat("Line {0},{1}\t: {2}\n", error.Line, error.Column, error.ErrorText);
                }
                throw new Exception(errors.ToString());
            }
            else
            {
                return results.CompiledAssembly;
            }
        }

and i'm getting some exceptions like this:

{Compiler Errors :

Line 13,10	: The type or namespace name 'Column' could not be found (are you missing a using directive or an assembly reference?)

Line 13,10	: The type or namespace name 'ColumnAttribute' could not be found (are you missing a using directive or an assembly reference?)

Line 15,10	: The type or namespace name 'DatabaseGenerated' could not be found (are you missing a using directive or an assembly reference?)

Line 15,10	: The type or namespace name 'DatabaseGeneratedAttribute' could not be found (are you missing a using directive or an assembly reference?)

Line 9,6	: The type or namespace name 'Table' could not be found (are you missing a using directive or an assembly reference?)

Line 9,6	: The type or namespace name 'TableAttribute' could not be found (are you missing a using directive or an assembly reference?)}

Any help?

Thank you.

---

-- Hamid Eghbalz Technical Manager Douran Co

Answer 1

On 4/27/2012 10:43 AM, ano0sh wrote:

> I'm try to compile this code at run time. this code is a code-first EF4

> class.

>

> using System;

> using System.Collections.Generic;

> using System.Linq;

> using System.Text;

> using System.ComponentModel.DataAnnotations;

>

> namespace EFCodeFirst.Model.Models

> {

>      [Table("Blog")]

>      public class Blog

>      {

>          public Guid Id { get; set; }

>          [Column("txtTitle")]

>          public string Title { get; set; }

>          [DatabaseGenerated(DatabaseGeneratedOption.None)]

>          public string ShortTitle { get { return Title; } }

>          public string BloggerName { get; set; }

>          public virtual ICollection<Post>  Posts { get; set; }

>      }

>

>      public class Post

>      {

>          public Guid Id { get; set; }

>          public string Title { get; set; }

>          public DateTime DateCreated { get; set; }

>          public string Content { get; set; }

>          public Guid BlogId { get; set; }

>      }

> }

>

>

> using this method that compile the given code. I tested this code with a

> simple class. it works. but with given class, it doesn't work at all.

>

> private Assembly BuildAssembly(string code)

>          {

>              Microsoft.CSharp.CSharpCodeProvider provider = new CSharpCodeProvider();

>              ICodeCompiler compiler = provider.CreateCompiler();

>              CompilerParameters compilerparams = new CompilerParameters();

>              compilerparams.GenerateExecutable = false;

>              compilerparams.GenerateInMemory = true;

>              CompilerResults results = compiler.CompileAssemblyFromSource(compilerparams, code);

>              if (results.Errors.HasErrors)

>              {

>                  StringBuilder errors = new StringBuilder("Compiler Errors :\r\n");

>                  foreach (CompilerError error in results.Errors)

>                  {

>                      errors.AppendFormat("Line {0},{1}\t: {2}\n", error.Line, error.Column, error.ErrorText);

>                  }

>                  throw new Exception(errors.ToString());

>              }

>              else

>              {

>                  return results.CompiledAssembly;

>              }

>          }

>

>

> and i'm getting some exceptions like this:

>

> error CS0234: The type or namespace name 'Linq' does not exist in the namespace 'System' (are you missing an assembly reference?)}

>

>

> Any help?

>

> Thank you.

>

>

> ------------------------------------------------------------------------

>

> -- Hamid Eghbalz Technical Manager Douran Co

>

 

I would suspect that you are going to have to set reference to

System.Linq in a config file that this second part uses and it's not there.

 

 

Answer 2

I added

 compilerparams.ReferencedAssemblies.Add("System.Linq");

to BuildAssembly method and get this exception:

{error CS0006: Metadata file 'System.Linq' could not be found}

---

-- Technical Manager

Answer 3

On 4/27/2012 1:13 PM, ano0sh wrote:

>

> I added

>

>   compilerparams.ReferencedAssemblies.Add("System.Linq");

>

> to BuildAssembly method and get this exception:

>

>

> {error CS0006: Metadata file 'System.Linq' could not be found}

 

Well I suspect that you are going to have to copy the System.Linq DLL to

where the exe is located so that it can be found. That's what happens

when you reference a .NET DLL. The DLL is copied to the Bin directory

where the exe is located so that .NET can find it for the application to

use, as an example.

 

Answer 4

is this necessary when i use .net ?

i have .net 4 installed on my machine.

.net dlls never copy to bin folder. am i right?

 

---

-- Technical Manager

Answer 5

On 4/27/2012 1:26 PM, ano0sh wrote:

> is this necessary when i use .net ?

 

Well any .NET DLL is never registered with the registry. But it must be

found by a .NET application. The last I remember, a .NET DLL has to be

in the location of the executable in order for it to be found. This may

only apply to classlib projects within a solution.

>

> i have .net 4 installed on my machine.

>

> .net dlls never copy to bin folder. am i right?

 

I don't know how .NET Framework 4.0 handles it now. Maybe the DLL needs

to be in the GAC so .NET can find it.

 

Answer 6

Hi guy,

  Please read this blog article talking about hwo to process Code-First Development with Entity Framework 4.

   http://weblogs.asp.net/scottgu/archive/2010/07/16/code-first-development-with-entity-framework-4.aspx

  Sincerely,

  Jason Wang

---

Jason Wang [MSFT]
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