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CSharp · Console

/Program.cs

using System;
using System.Collections.Generic;
using System.Linq;
using Newtonsoft.Json; 
					
public class Program
{
	
	public static void Main()
	{
		var info = new DocInfo(){
			CustomerInfo = new CustomerInfo(){Name = "A", Adress = "B"},
			ProductInfo = new ProductInfo(){Name = "A", Price = "1"},
			Whatever = new Whatever(){Property1 = "1", Property2 = "2"}	
		};
		var output =  JsonConvert.SerializeObject(info);
		Console.WriteLine(output);
	}
}

public class DocInfo{
	public CustomerInfo CustomerInfo{get;set;}
	public ProductInfo ProductInfo{get;set;}
	public Whatever Whatever{get;set;}
}

public class CustomerInfo{
	public string Name{get;set;}
	public string Adress{get;set;}
	
}
	

public class ProductInfo{
	public string Name{get;set;}
	public string Price{get;set;}
	
}


public class Whatever{
	public string Property1{get;set;}
	public string Property2{get;set;}
	
}