ConstructorBuilder

ConstructorBuilderRequest is a request to create a ConstructorBuilder.

// Request to create constructor builder
IRequestFor<ConstructorBuilder> ctor = new ConstructorBuilderRequest(
    methodAttributes: MethodAttributes.Public,
    attributes: new object[] { new PropertyAttribute("Key", "Value") },
    callingConventions: null,
    parameterTypes: typeof(int));

Opcodes are added to constructor.

// ".ctor(int x) { MyField = x < 5 ? 0 : 1; }"
IRequestFor<ILGenerator> ops = ILGeneratorRequest.Default
    .Append(OpCodes.Ldarg_0)
    .Append(OpCodes.Ldarg_1)
    .Append(OpCodes.Ldc_I4_5)
    .Append(OpCodes.Cgt)
    .Append(OpCodes.Stfld, field)
    .Append(OpCodes.Ret);
// Add ops to .ctor
ctor = ctor.Append(ops);

Constructor is added to type.

// Request to create type builder
IRequestFor<TypeBuilder> typeBuilder = new TypeBuilderRequest("MyClass03", TypeAttributes.Public | TypeAttributes.Class | TypeAttributes.AutoClass);
// Add field to type request
typeBuilder = typeBuilder.Append(field);
// Add .ctor to type request
typeBuilder = typeBuilder.Append(ctor);

Type is instantiated with constructor arguments.

// Request to build type
IRequestFor<Type> type = new TypeRequest(typeBuilder);
// Request to create new instance
IRequestFor<Object> newRequest = type.NewRequest(null, Parameters: 9);
// Get instance
object instance = service.GetRequired<IRequestFor<object>, object>(newRequest);
// Read with reflection
int value = (int)instance.GetType().GetField("MyField")!.GetValue(instance)!;
// Print 
Console.WriteLine(value);

Full Example

Full example

using System;
using System.Reflection;
using System.Reflection.Emit;
using Avalanche;
using Avalanche.Emit;
using Avalanche.Service;

public class constructorbuilder
{
    public static void Run()
    {
        {
            // Create service
            IService service = Services.Create(Avalanche.Emit.Module.Instance);
            // <01>
            // Request to create constructor builder
            IRequestFor<ConstructorBuilder> ctor = new ConstructorBuilderRequest(
                methodAttributes: MethodAttributes.Public,
                attributes: new object[] { new PropertyAttribute("Key", "Value") },
                callingConventions: null,
                parameterTypes: typeof(int));
            // </01>
            // Request to create field
            IRequestFor<FieldBuilder> field = new FieldBuilderRequest("MyField", typeof(int), FieldAttributes.Public);
            // <02>
            // ".ctor(int x) { MyField = x < 5 ? 0 : 1; }"
            IRequestFor<ILGenerator> ops = ILGeneratorRequest.Default
                .Append(OpCodes.Ldarg_0)
                .Append(OpCodes.Ldarg_1)
                .Append(OpCodes.Ldc_I4_5)
                .Append(OpCodes.Cgt)
                .Append(OpCodes.Stfld, field)
                .Append(OpCodes.Ret);
            // Add ops to .ctor
            ctor = ctor.Append(ops);
            // </02>
            // <03>
            // Request to create type builder
            IRequestFor<TypeBuilder> typeBuilder = new TypeBuilderRequest("MyClass03", TypeAttributes.Public | TypeAttributes.Class | TypeAttributes.AutoClass);
            // Add field to type request
            typeBuilder = typeBuilder.Append(field);
            // Add .ctor to type request
            typeBuilder = typeBuilder.Append(ctor);
            // </03>

            // <04>
            // Request to build type
            IRequestFor<Type> type = new TypeRequest(typeBuilder);
            // Request to create new instance
            IRequestFor<Object> newRequest = type.NewRequest(null, Parameters: 9);
            // Get instance
            object instance = service.GetRequired<IRequestFor<object>, object>(newRequest);
            // Read with reflection
            int value = (int)instance.GetType().GetField("MyField")!.GetValue(instance)!;
            // Print 
            Console.WriteLine(value);
            // </04>
        }
    }
}