Fields and properties get and set functions using expression

ExpressionGetSet.cs

using System;
using System.Linq;
using System.Collections.Generic;
using System.Diagnostics;
using System.Reflection;
using System.Linq.Expressions;

namespace Aptivi;

class ExpressionGetSet
{
    // --------------------------- Test classes ---------------------------
	
    public static class Person
    {
        public static String Title = "Product Manager";
        public static String Name { get; set; } = "John";
    }
    
    public class App
    {
    	public String Desc = "Chat on IRC from anywhere, and never miss a message";
        public String Name { get; set; } = "IRCCloud";
    }
    
    // --------------------------- Get and set property using expression in static mode ---------------------------
    
    private static object ExpressionGetPropertyStatic(Type type, string property)
    {
        if (type is null)
        	throw new ArgumentNullException(nameof(type));
        if (property is null)
        	throw new ArgumentNullException(nameof(property));
        	    
        var propertyInfo = type.GetProperty(property);
            
        var instanceParam = Expression.Parameter(type);
            
        var callExpr = Expression.Call(propertyInfo.GetGetMethod());
        var convExpr = Expression.Convert(callExpr, typeof(Object));

        var expression = Expression.Lambda<Func<Object>>(convExpr).Compile();
            
        return expression();
    }
    
    private static void ExpressionSetPropertyStatic(Type type, string property, object value)
    {
        if (type is null)
        	throw new ArgumentNullException(nameof(type));
        if (property is null)
        	throw new ArgumentNullException(nameof(property));
        if (value is null)
        	throw new ArgumentNullException(nameof(value));
        	    
        var propertyInfo = type.GetProperty(property);

        var argumentParam = Expression.Parameter(typeof(Object));
            
        var convExpr = Expression.Convert(argumentParam, propertyInfo.PropertyType);
        var callExpr = Expression.Call(propertyInfo.GetSetMethod(), convExpr);

        var expression = Expression.Lambda<Action<object>>(callExpr, argumentParam).Compile();

        expression(value);
    }
    
    // --------------------------- Get and set property using expression in instance mode ---------------------------
    
    private static object ExpressionGetPropertyInstance<T>(T instance, string property)
    {
        if (instance is null)
        	throw new ArgumentNullException(nameof(instance));
        if (property is null)
        	throw new ArgumentNullException(nameof(property));
        	    
        var type = instance.GetType();
        var propertyInfo = type.GetProperty(property);
            
        var instanceParam = Expression.Parameter(type);
            
        var callExpr = Expression.Call(instanceParam, propertyInfo.GetGetMethod());
        var convExpr = Expression.Convert(callExpr, typeof(Object));

        var expression = Expression.Lambda<Func<T, Object>>(convExpr, instanceParam).Compile();
            
        return expression(instance);
    }
    
    private static void ExpressionSetPropertyInstance<T>(T instance, string property, object value)
    {
        if (instance is null)
        	throw new ArgumentNullException(nameof(instance));
        if (property is null)
        	throw new ArgumentNullException(nameof(property));
        if (value is null)
        	throw new ArgumentNullException(nameof(value));
        	    
        var type = instance.GetType();
        var propertyInfo = type.GetProperty(property);

        var instanceParam = Expression.Parameter(type);
        var argumentParam = Expression.Parameter(typeof(Object));
            
        var convExpr = Expression.Convert(argumentParam, propertyInfo.PropertyType);
        var callExpr = Expression.Call(instanceParam, propertyInfo.GetSetMethod(), convExpr);

        var expression = Expression.Lambda<Action<T, object>>(callExpr, instanceParam, argumentParam).Compile();

        expression(instance, value);
    }
    
    // --------------------------- Get and set field using expression in static mode ---------------------------
    
    private static object ExpressionGetFieldStatic(Type type, string field)
    {
        if (type is null)
        	throw new ArgumentNullException(nameof(type));
        if (field is null)
        	throw new ArgumentNullException(nameof(field));
        	    
        var fieldInfo = type.GetField(field);
            
        var assignExpr = Expression.Field(null, fieldInfo.DeclaringType, fieldInfo.Name);
        var convExpr = Expression.Convert(assignExpr, typeof(object));

        var expression = Expression.Lambda<Func<object>>(convExpr).Compile();

        return expression();
    }
    
    private static void ExpressionSetFieldStatic(Type type, string field, object value)
    {
        if (type is null)
        	throw new ArgumentNullException(nameof(type));
        if (field is null)
        	throw new ArgumentNullException(nameof(field));
        if (value is null)
        	throw new ArgumentNullException(nameof(value));
        	    
        var fieldInfo = type.GetField(field);
            
        var argumentParam = Expression.Parameter(typeof(object));
            
        var assignExpr = Expression.Field(null, fieldInfo.DeclaringType, fieldInfo.Name);
        var convertExpr = Expression.Convert(argumentParam, assignExpr.Type);
        var setExpr = Expression.Assign(assignExpr, convertExpr);

        var expression = Expression.Lambda<Action<object>>(setExpr, argumentParam).Compile();

        expression(value);
    }
    
    // --------------------------- Get and set field using expression in instance mode ---------------------------
    
    private static object ExpressionGetFieldInstance<T>(T instance, string field)
    {
        if (instance is null)
        	throw new ArgumentNullException(nameof(instance));
        if (field is null)
        	throw new ArgumentNullException(nameof(field));
        	    
        var type = instance.GetType();
        var fieldInfo = type.GetField(field);
            
        var instanceParam = Expression.Parameter(type);
            
        var assignExpr = Expression.Field(instanceParam, fieldInfo);
        var convExpr = Expression.Convert(assignExpr, typeof(object));

        var expression = Expression.Lambda<Func<T, object>>(convExpr, instanceParam).Compile();

        return expression(instance);
    }
    
    private static void ExpressionSetFieldInstance<T>(T instance, string field, object value)
    {
        if (instance is null)
        	throw new ArgumentNullException(nameof(instance));
        if (field is null)
        	throw new ArgumentNullException(nameof(field));
        if (value is null)
        	throw new ArgumentNullException(nameof(value));
        	    
        var type = instance.GetType();
        var fieldInfo = type.GetField(field);
            
        var instanceParam = Expression.Parameter(type);
        var argumentParam = Expression.Parameter(typeof(object));
            
        var convExpr = Expression.Convert(argumentParam, fieldInfo.FieldType);
        var assignExpr = Expression.Field(instanceParam, fieldInfo);
        var setExpr = Expression.Assign(assignExpr, convExpr);

        var expression = Expression.Lambda<Action<T, object>>(setExpr, instanceParam, argumentParam).Compile();

        expression(instance, value);
    }

    // --------------------------- CUT HERE ---------------------------
    
    public static void Main()
    {
    	Console.WriteLine("---------- Static set/get using expression on properties ----------");
        Console.WriteLine($"Person name before set: {Person.Name}");
        Console.WriteLine($"Person name using exp:  {ExpressionGetPropertyStatic(typeof(Person), "Name")}");
        ExpressionSetPropertyStatic(typeof(Person), "Name", "Trevor");
        Console.WriteLine($"Person name after set:  {Person.Name}");
        Console.WriteLine($"Person name using exp:  {ExpressionGetPropertyStatic(typeof(Person), "Name")}");
        Console.WriteLine();
        
    	Console.WriteLine("---------- Instance set/get using expression on properties ----------");
    	var aid = new App();
        Console.WriteLine($"App name before set:    {aid.Name}");
        Console.WriteLine($"App name using exp:     {ExpressionGetPropertyInstance(aid, "Name")}");
        ExpressionSetPropertyInstance(aid, "Name", "Mastodon");
        Console.WriteLine($"App name after set:     {aid.Name}");
        Console.WriteLine($"App name using exp:     {ExpressionGetPropertyInstance(aid, "Name")}");
        Console.WriteLine();
        
    	Console.WriteLine("---------- Static set/get using expression on fields ----------");
        Console.WriteLine($"Person name before set: {Person.Title}");
        Console.WriteLine($"Person name using exp:  {ExpressionGetFieldStatic(typeof(Person), "Title")}");
        ExpressionSetFieldStatic(typeof(Person), "Title", "Fabrikam CEO");
        Console.WriteLine($"Person name after set:  {Person.Title}");
        Console.WriteLine($"Person name using exp:  {ExpressionGetFieldStatic(typeof(Person), "Title")}");
        Console.WriteLine();
        
    	Console.WriteLine("---------- Instance set/get using expression on fields ----------");
        Console.WriteLine($"App name before set:    {aid.Desc}");
        Console.WriteLine($"App name using exp:     {ExpressionGetFieldInstance(aid, "Desc")}");
        ExpressionSetFieldInstance(aid, "Desc", "Decentralized social network");
        Console.WriteLine($"App name after set:     {aid.Desc}");
        Console.WriteLine($"App name using exp:     {ExpressionGetFieldInstance(aid, "Desc")}");
        Console.WriteLine();
    }
}