PropertyBuilder

PropertyBuilderRequest is a request to create PropertyBuilder.

// Create service
IService service = Services.Create((ServiceHandlers.Instance, EmitHandlers.Instance), CachePolicies.Default);
// Request to create type builder
IRequestFor<TypeBuilder> typeBuilder = new TypeBuilderRequest("MyClassWithProperty", TypeAttributes.Public | TypeAttributes.Class | TypeAttributes.AutoClass);

// Initialize property request
IRequestFor<PropertyBuilder> property = new PropertyBuilderRequest(
    Name: "MyProperty",
    Attributes: PropertyAttributes.None,
    PropertyType: typeof(int),
    ParameterTypes: null);

In this example we create a backing field.

// Request to create backing field
IRequestFor<FieldBuilder> field = new FieldBuilderRequest("MyField", typeof(int), FieldAttributes.Public);
// Add backing field to type request
typeBuilder = typeBuilder.Append(field);

PropertyBuilderSetSetter is a request to attach a setter method to property.

// Create set method
IRequestFor<MethodBuilder> setter = new MethodBuilderRequest(
    Name: "set_MyProperty",
    Attributes: MethodAttributes.SpecialName | MethodAttributes.HideBySig | MethodAttributes.Public,
    ReturnType: null,
    ParameterTypes: typeof(int));
// Create op codes
IRequestFor<ILGenerator> il = ILGeneratorRequest.Default
    .Append(OpCodes.Ldarg_0)
    .Append(OpCodes.Ldarg_1)
    .Append(OpCodes.Stfld, field)
    .Append(OpCodes.Ret);
// Add opcodes to method request
setter = setter.Append(il);
// Add setter request to type
typeBuilder.Append(setter);
// Assign setter to property
property = property.Append(new PropertyBuilderSetSetter(setter));

And PropertyBuilderSetGetter is a request to attach a getter method.

// Create get method
IRequestFor<MethodBuilder> getter = new MethodBuilderRequest(
    Name: "get_MyProperty",
    Attributes: MethodAttributes.SpecialName | MethodAttributes.HideBySig | MethodAttributes.Public,
    ReturnType: typeof(int));
// Create op codes
IRequestFor<ILGenerator> il = ILGeneratorRequest.Default
    .Append(OpCodes.Ldarg_0)
    .Append(OpCodes.Ldfld, field)
    .Append(OpCodes.Ret);
// Add opcodes to method request
getter = getter.Append(il);
// Add getter request to type
typeBuilder.Append(getter);
// Assign setter to property
property = property.Append(new PropertyBuilderSetGetter(getter));

Once property request is complete, add it to type request.

// Add property to type request
typeBuilder = typeBuilder.Append(property);

Request an instance and try it.

// Request to build type
IRequestFor<Type> type = new TypeRequest(typeBuilder);
// Request to create new instance
IRequestFor<Object> newRequest = type.NewRequest();
// Print 
Console.WriteLine(newRequest.PrintTree());
// Get instance
object instance = service.GetRequired<IRequestFor<object>, object>(newRequest);
// Get property with reflection
PropertyInfo pi = instance.GetType().GetProperty("MyProperty")!;
// Write with reflection
pi.SetValue(instance, 9);
// Read with reflection
int value = (int)pi.GetValue(instance)!;

View complete request

NewRequest
└── Type = TypeRequest
    └── Key = ContextRequest
        ├── Key = "System.Reflection.Emit.TypeBuilder"
        ├── Value = TypeBuilderRequest
        │   ├── Name = "MyClassWithProperty"
        │   └── Attributes = AutoLayout, AnsiClass, Class, Public, AutoClass
        ├── Requests[0] = FieldBuilderRequest
        │   ├── Name = "MyField"
        │   ├── Attributes = Public
        │   └── FieldType = System.Int32
        └── Requests[1] = ContextRequest
            ├── Key = "System.Reflection.Emit.PropertyBuilder"
            ├── Value = PropertyBuilderRequest
            │   ├── Name = "MyProperty"
            │   ├── Attributes = None
            │   └── PropertyType = System.Int32
            ├── Requests[0] = PropertyBuilderSetSetter
            │   └── Setter = ContextRequest
            │       ├── Key = "System.Reflection.Emit.Builder"
            │       ├── Value = MethodBuilderRequest
            │       │   ├── Name = "set_MyProperty"
            │       │   ├── Attributes = PrivateScope, Public, HideBySig, SpecialName
            │       │   └── ParameterTypes[0] = System.Int32
            │       └── Requests[0] = ContextRequest
            │           ├── Key = "System.Reflection.Emit.ILGenerator"
            │           ├── Value = ILGeneratorRequest
            │           ├── Requests[0] = Emit
            │           │   └── Opcode = ldarg.0
            │           ├── Requests[1] = Emit
            │           │   └── Opcode = ldarg.1
            │           ├── Requests[2] = Emit
            │           │   ├── Opcode = stfld
            │           │   └── Parameters[0] = FieldBuilderRequest
            │           └── Requests[3] = Emit
            │               └── Opcode = ret
            └── Requests[1] = PropertyBuilderSetGetter
                └── Getter = ContextRequest
                    ├── Key = "System.Reflection.Emit.Builder"
                    ├── Value = MethodBuilderRequest
                    │   ├── Name = "get_MyProperty"
                    │   ├── Attributes = PrivateScope, Public, HideBySig, SpecialName
                    │   └── ReturnType = System.Int32
                    └── Requests[0] = ContextRequest
                        ├── Key = "System.Reflection.Emit.ILGenerator"
                        ├── Value = ILGeneratorRequest
                        ├── Requests[0] = Emit
                        │   └── Opcode = ldarg.0
                        ├── Requests[1] = Emit
                        │   ├── Opcode = ldfld
                        │   └── Parameters[0] = FieldBuilderRequest
                        └── Requests[2] = Emit
                            └── Opcode = ret

Full Example

Full example

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

public class propertybuilder
{
    public static void Run()
    {
        {
            // <1>
            // Create service
            IService service = Services.Create((ServiceHandlers.Instance, EmitHandlers.Instance), CachePolicies.Default);
            // Request to create type builder
            IRequestFor<TypeBuilder> typeBuilder = new TypeBuilderRequest("MyClassWithProperty", TypeAttributes.Public | TypeAttributes.Class | TypeAttributes.AutoClass);

            // Initialize property request
            IRequestFor<PropertyBuilder> property = new PropertyBuilderRequest(
                Name: "MyProperty",
                Attributes: PropertyAttributes.None,
                PropertyType: typeof(int),
                ParameterTypes: null);
            // </1>
            // <2>
            // Request to create backing field
            IRequestFor<FieldBuilder> field = new FieldBuilderRequest("MyField", typeof(int), FieldAttributes.Public);
            // Add backing field to type request
            typeBuilder = typeBuilder.Append(field);
            // </2>
            {
                // <3>
                // Create set method
                IRequestFor<MethodBuilder> setter = new MethodBuilderRequest(
                    Name: "set_MyProperty",
                    Attributes: MethodAttributes.SpecialName | MethodAttributes.HideBySig | MethodAttributes.Public,
                    ReturnType: null,
                    ParameterTypes: typeof(int));
                // Create op codes
                IRequestFor<ILGenerator> il = ILGeneratorRequest.Default
                    .Append(OpCodes.Ldarg_0)
                    .Append(OpCodes.Ldarg_1)
                    .Append(OpCodes.Stfld, field)
                    .Append(OpCodes.Ret);
                // Add opcodes to method request
                setter = setter.Append(il);
                // Add setter request to type
                typeBuilder.Append(setter);
                // Assign setter to property
                property = property.Append(new PropertyBuilderSetSetter(setter));
                // </3>
            }
            {
                // <4>
                // Create get method
                IRequestFor<MethodBuilder> getter = new MethodBuilderRequest(
                    Name: "get_MyProperty",
                    Attributes: MethodAttributes.SpecialName | MethodAttributes.HideBySig | MethodAttributes.Public,
                    ReturnType: typeof(int));
                // Create op codes
                IRequestFor<ILGenerator> il = ILGeneratorRequest.Default
                    .Append(OpCodes.Ldarg_0)
                    .Append(OpCodes.Ldfld, field)
                    .Append(OpCodes.Ret);
                // Add opcodes to method request
                getter = getter.Append(il);
                // Add getter request to type
                typeBuilder.Append(getter);
                // Assign setter to property
                property = property.Append(new PropertyBuilderSetGetter(getter));
                // </4>
            }
            // <5>
            // Add property to type request
            typeBuilder = typeBuilder.Append(property);
            // </5>
            // <6>
            // Request to build type
            IRequestFor<Type> type = new TypeRequest(typeBuilder);
            // Request to create new instance
            IRequestFor<Object> newRequest = type.NewRequest();
            // Print 
            Console.WriteLine(newRequest.PrintTree());
            // Get instance
            object instance = service.GetRequired<IRequestFor<object>, object>(newRequest);
            // Get property with reflection
            PropertyInfo pi = instance.GetType().GetProperty("MyProperty")!;
            // Write with reflection
            pi.SetValue(instance, 9);
            // Read with reflection
            int value = (int)pi.GetValue(instance)!;
            // </6>
            // Print 
            Console.WriteLine(newRequest.PrintTree());
        }
    }
}