Clean, efficient, infallible method of programmatically generating C# code files

Question

I want to know if there is any good way of programmatically producing C# code without actually manipulating strings or StringBuilders. Additionally it should check if the code compiles, but I guess this can be done using CSharpCodeProvider.

I'm looking for something like the following:

CodeUnit unit = new CodeUnit();
unit.AddDefaultUsings();
unit.AddUsing("MyApi.CoolNameSpace", "MyApi.Yay");
var clazz = unit.AddClass("GeneratedClass", Access.Public);
clazz.AddConstructor("....");
if(unit.Compile() != true)
    //oh dang, somethings wrong!
else unit.WriteUTF8To("GeneratedClass.cs");

This might be part of the core library (Don't think CSharpCodeProvider can do this?) or an external library, but this is not my forte at all (dynamically producing code using c#), so if this seems clueless it's because I am!

What's wrong with strings? If you don't know the names of these things ahead of time I fail to see how you are going to use enumerated or constant values. — Ed Swangren
– Ed Swangren, Commented Jul 17, 2011 at 19:13

svick · Accepted Answer · 2011-07-17 19:58:25Z

That's exactly what CodeDOM is for:

var unit = new CodeCompileUnit();

var @namespace = new CodeNamespace("GeneratedCode");
unit.Namespaces.Add(@namespace);

// AddDefault() doesn't exist, but you can create it as an extension method
@namespace.Imports.AddDefault();
@namespace.Imports.Add(new CodeNamespaceImport("MyApi.CoolNameSpace"));

var @class = new CodeTypeDeclaration("GeneratedClass");
@namespace.Types.Add(@class);

@class.TypeAttributes = TypeAttributes.Class | TypeAttributes.Public;

var constructor = new CodeConstructor();
constructor.Attributes = MemberAttributes.Public;
constructor.Parameters.Add(
    new CodeParameterDeclarationExpression(typeof(string), "name"));

constructor.Statements.Add(…);

@class.Members.Add(constructor);

var provider = new CSharpCodeProvider();

var result = provider.CompileAssemblyFromDom(new CompilerParameters(), unit);

Although it can be quite verbose. Also, it tries to be language-independent, which means you can't use C#-specific features like static classes, extension methods, LINQ query expressions or lambdas using this API. What you can do though, is to put any string inside method body. Using this, you can use some of the C#-specific features, but only using string manipulation, which you were trying to avoid.

Archie · Accepted Answer · 2011-07-17 19:16:31Z

0

You can use Reflection.Emit classes like MethodBuilder. Also expression trees with them. It is rather CLS than C#.

answered Jul 17, 2011 at 19:16

Archie

663 bronze badges

Comments

jgauffin · Accepted Answer · 2011-07-17 19:19:43Z

I've done a wrapper around codedom. You only need to create your own C# script and specify the types being used. Namespaces and assemblies will automatically be included.

Example

public interface IWorld
{
    string Hello(string value);
}

string code = @"namespace MyNamespace
{
  class Temp : IWorld
  {
      public string Hello(string value)
      {
          return ""World "" + value;
      }
  }
}";

Compiler compiler = new Compiler();
compiler.AddType(typeof(string));
compiler.Compile(code);
var obj = compiler.CreateInstance<IWorld>();
string result = obj.Hello("World!");

Note that it was a long time ago that I wrote it. The example might not work 100%. (The Compiler class do work, the example might use it incorrectly).

Source code:

http://fadd.codeplex.com/SourceControl/changeset/view/67972#925984

svick · Accepted Answer · 2011-08-28 22:12:13Z

0

I like to use the NVelocity Template Engine.

edited Aug 28, 2011 at 22:12

svick

247k54 gold badges405 silver badges535 bronze badges

answered Jul 17, 2011 at 19:14

armandomiani

7306 silver badges16 bronze badges

Collectives™ on Stack Overflow

Clean, efficient, infallible method of programmatically generating C# code files

4 Answers 4

Comments

Comments

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

4 Answers 4

Comments

Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related