return IQueryable after GroupBy SO 27818106 | C# Online Compiler

return IQueryable after GroupBy SO 27818106 by Ehsan Sajjad

using System;
using System.Linq;
using System.Collections.Generic;

public class Program
{
	public static void Main()
	{
	foreach (var item in GetAll())
		{
			Console.WriteLine("CategoryName: {0}", item.Key);
			//Console.WriteLine("ColorName: {0}", );
			foreach(var product in item)
			{
				Console.WriteLine("Product: |_ {0} - {1}", product.ProductName,product.ColorName);
			}
		}
	}

	public static IQueryable<IGrouping<string,GroupViewModel>> GetAll()
	{
		List<Category> listCategories = new List<Category>
		{
		new Category
		{
		Id = 1, CateName = "SmartPhone"
		}

		, new Category
		{
		Id = 2, CateName = "Laptop"
		}

		, new Category
		{
		Id = 3, CateName = "Desktop"
		}

		, }

		;
		List<Product> listProducts = new List<Product>
		{
		new Product
		{
		Id = 1, ProdName = "Lumia 720", CategoryId = 1, ColorId = 2
		}

		, new Product
		{
		Id = 2, ProdName = "PC HP", CategoryId = 3, ColorId = 1
		}

		, new Product
		{
		Id = 3, ProdName = "PC Dell", CategoryId = 3, ColorId = 1
		}

		, new Product
		{
		Id = 4, ProdName = "Laptop Lenovo", CategoryId = 2, ColorId = 2
		}

		, new Product
		{
		Id = 5, ProdName = "Lumia 920", CategoryId = 1, ColorId = 2
		}

		, new Product
		{
		Id = 6, ProdName = "Laptop Dell", CategoryId = 2, ColorId = 3
		}

		, new Product
		{
		Id = 7, ProdName = "Laptop HP", CategoryId = 2, ColorId = 3
		}
		}

		;
		List<Color> listColor = new List<Color>
		{
		new Color
		{
		ColorId = 1, ColorName = "Blue"
		}

		, new Color
		{
		ColorId = 2, ColorName = "Yellow"
		}

		, new Color
		{
		ColorId = 3, ColorName = "Red"
		}
		}

		;
		var query = (
			from p in listProducts
			join cl in listColor on p.ColorId equals cl.ColorId
			join c in listCategories on p.CategoryId equals c.Id into e
			from j in e.DefaultIfEmpty()select new GroupViewModel
			{
			ProductId = p.Id, ProductName = p.ProdName, CategoryId = j.Id, CateogryName = j.CateName, ColorId = cl.ColorId, ColorName = cl.ColorName
			}

		).GroupBy(x => x.CateogryName);
		
		return query.AsQueryable<IGrouping<string,GroupViewModel>>();
	}
}

public class Color
{
	public int ColorId
	{
		get;
		set;
	}

	public string ColorName
	{
		get;
		set;
	}
}

public class Category
{
	public int Id
	{
		get;
		set;
	}

	public string CateName
	{
		get;
		set;
	}
}

public class Product
{
	public int Id
	{
		get;
		set;
	}

	public string ProdName
	{
		get;
		set;
	}

	public int CategoryId
	{
		get;
		set;
	}

	public int ColorId
	{
		get;
		set;
	}
}

public class GroupViewModel
{
	public int ProductId
	{
		get;
		set;
	}

	public string ProductName
	{
		get;
		set;
	}

	public int CategoryId
	{
		get;
		set;
	}

	public string CateogryName
	{
		get;
		set;
	}

	public int ColorId
	{
		get;
		set;
	}

	public string ColorName
	{
		get;
		set;
	}
}

public class GroupModel
{
	public int CategoryId
	{
		get;
		set;
	}

	public string CateogryName
	{
		get;
		set;
	}

	public int ColorId
	{
		get;
		set;
	}

	public string ColorName
	{
		get;
		set;
	}

	public List<Product> Products
	{
		get;
		set;
	}
}

​x
 
using System;
using System.Linq;
using System.Collections.Generic;
​
public class Program
{
    public static void Main()
    {
    foreach (var item in GetAll())
        {
            Console.WriteLine("CategoryName: {0}", item.Key);
            //Console.WriteLine("ColorName: {0}", );
            foreach(var product in item)
            {
                Console.WriteLine("Product: |_ {0} - {1}", product.ProductName,product.ColorName);
            }
        }
    }
​
    public static IQueryable<IGrouping<string,GroupViewModel>> GetAll()
    {
        List<Category> listCategories = new List<Category>
        {
        new Category
        {
        Id = 1, CateName = "SmartPhone"
        }
​
        , new Category
        {
        Id = 2, CateName = "Laptop"
        }
​
        , new Category
        {
        Id = 3, CateName = "Desktop"
        }
​
        , }
​
        ;
        List<Product> listProducts = new List<Product>
        {
        new Product
        {
        Id = 1, ProdName = "Lumia 720", CategoryId = 1, ColorId = 2
        }
​
        , new Product
        {
        Id = 2, ProdName = "PC HP", CategoryId = 3, ColorId = 1
        }
​
        , new Product
        {
        Id = 3, ProdName = "PC Dell", CategoryId = 3, ColorId = 1
        }
​
        , new Product
        {
        Id = 4, ProdName = "Laptop Lenovo", CategoryId = 2, ColorId = 2
        }
​
        , new Product
        {
        Id = 5, ProdName = "Lumia 920", CategoryId = 1, ColorId = 2
        }
​
        , new Product
        {
        Id = 6, ProdName = "Laptop Dell", CategoryId = 2, ColorId = 3
        }
​
        , new Product
        {
        Id = 7, ProdName = "Laptop HP", CategoryId = 2, ColorId = 3
        }
        }
​
        ;
        List<Color> listColor = new List<Color>
        {
        new Color
        {
        ColorId = 1, ColorName = "Blue"
        }
​
        , new Color
        {
        ColorId = 2, ColorName = "Yellow"
        }
​
        , new Color
        {
        ColorId = 3, ColorName = "Red"
        }
        }
​
        ;
        var query = (
            from p in listProducts
            join cl in listColor on p.ColorId equals cl.ColorId
            join c in listCategories on p.CategoryId equals c.Id into e
            from j in e.DefaultIfEmpty()select new GroupViewModel
            {
            ProductId = p.Id, ProductName = p.ProdName, CategoryId = j.Id, CateogryName = j.CateName, ColorId = cl.ColorId, ColorName = cl.ColorName
            }
​
        ).GroupBy(x => x.CateogryName);
        
        return query.AsQueryable<IGrouping<string,GroupViewModel>>();
    }
}
​
public class Color
{
    public int ColorId
    {
        get;
        set;
    }
​
    public string ColorName
    {
        get;
        set;
    }
}
​
public class Category
{
    public int Id
    {
        get;
        set;
    }
​
    public string CateName
    {
        get;
        set;
    }
}
​
public class Product
{
    public int Id
    {
        get;
        set;
    }
​
    public string ProdName
    {
        get;
        set;
    }
​
    public int CategoryId
    {
        get;
        set;
    }
​
    public int ColorId
    {
        get;
        set;
    }
}
​
public class GroupViewModel
{
    public int ProductId
    {
        get;
        set;
    }
​
    public string ProductName
    {
        get;
        set;
    }
​
    public int CategoryId
    {
        get;
        set;
    }
​
    public string CateogryName
    {
        get;
        set;
    }
​
    public int ColorId
    {
        get;
        set;
    }
​
    public string ColorName
    {
        get;
        set;
    }
}
​
public class GroupModel
{
    public int CategoryId
    {
        get;
        set;
    }
​
    public string CateogryName
    {
        get;
        set;
    }
​
    public int ColorId
    {
        get;
        set;
    }
​
    public string ColorName
    {
        get;
        set;
    }
​
    public List<Product> Products
    {
        get;
        set;
    }
}

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