How to display product using group by prices in c# console app-CodePudding

I have list of products which has id, name and price. I want to show it in console using prices such as

Price 1 to 100 --list of products

price 101 to 200 --list of products and it so on till last highest price. I need to determine at runtime how many segments I need to create based upon highest price.

CodePudding user response：

If you have a list called products that have a property called Price you could use a basic Linq expression with OrderBy and Where

Edit: now that I understand your question better, you could create a new list for each segment of 100's.

so something like this:

products = products.OrderBy(x => x.Price).ToList();
var subProducts = products.Where(x => x.Price > 0 && x.Price < 100).ToList();
// then print each item in the list here.
// then do the next segment
subProducts = products.Where(x => x.Price >= 100 && x.Price < 200).ToList();

and you could put this basic format in a loop and then iterate through by the 100's to get each segment.

CodePudding user response：

There are two problems to solve here. First, you need to figure out, for any given price, how to categorize it into a price range. The information you've given in your post isn't quite specific enough unless all your prices are in whole numbers, but I'll make an educated guess here.

// Model
record ProductPriceRange(decimal Low, decimal High);

// Desired behavior
GetPriceRange(0.01m).Should().Be(new ProductPriceRange(0.01m, 100m));
GetPriceRange(100m).Should().Be(new ProductPriceRange(0.01m, 100m));
GetPriceRange(100.01m).Should().Be(new ProductPriceRange(100.01m, 200m));

// Implementation
ProductPriceRange GetPriceRange(decimal price)
{
    var groupBasis = (int)(((price - 0.01m) / 100)) * 100   0.01m;
    return new ProductPriceRange(groupBasis, groupBasis   99.99m);
}

Then your grouping code can look something like this:

var productGroups =
    from p in products
    group p by GetPriceRange(p.Price) into g
    select new {
        PriceRange = g.Key,
        Products = g.ToList()
    };
foreach (var g in productGroups)
{
    Console.WriteLine($"{g.PriceRange.Low} - {g.PriceRange.High}: {string.Join(", ", g.Products)}");
}

Sample output:

0.01 - 100.00: Product { Price = 0.01 }, Product { Price = 99.99 }, Product { Price = 100 }
100.01 - 200.00: Product { Price = 100.01 }, Product { Price = 199.99 }, Product { Price = 200 }
200.01 - 300.00: Product { Price = 200.01 }

CodePudding user response：

Try the following:

var query = products
   .GroupBy(p => (int)(p.Price / 100))
   .OrderBy(g => g.Key)
   .Select(g => new {
      Lower = g.Min(x => x.Price),
      Higher = g.Max(x => x.Price),
      Items = g.OrderBy(x => x.Price).ToList())
   })
   .ToList();

It will return list of lists.