C# Xamarin Select multiple values of same type from List

Question

I was wondering how to select multiple values of same type from a list...

To be more specific:

public class price
{
    public string NAME { get; set; }
    public string PRICE { get; set; }
    public string TIMESTAMP { get; set; }
}

This is my List called price. Now I want for example, if this is my json output to send to list:

{
"Products": [[{
            "NAME": "Shirt",
            "PRICE": "25.0",
            "TIMESTAMP": "2018-03-19 06:58:24"
        }
    ], [{
            "NAME": "Pants",
            "PRICE": "30.0",
            "TIMESTAMP": "2018-03-19 06:58:16"
        }
    ], [{
            "NAME": "Shirt",
            "PRICE": "20.0",
            "TIMESTAMP": "2018-03-19 06:58:17"
        }
    ]]
}

So I want to return the values from a specific Name, like Shirt. When I choose Shirt, I want the values: 25.0 - 20.0. Then I want to create a graph with all the values from NAME=Shirt orderby oldest first (Like a chart). I receive a json from a link, parse it and put it in a List like this:

string link = @"http://*****/getprices.php";
string json = new WebClient().DownloadString(link);
var jObject = JObject.Parse(json);
var pricePropery = jObject["Prices"] as JArray;
List<price> PriceList = new List<price>();
foreach (var property in pricePropery) 
{
    var propertyList = JsonConvert.DeserializeObject<List<price>>(property.ToString());

    PriceList.AddRange(propertyList);
}

The thing is that the json has a couple times the same NAME with only a different PRICE and TIMESTAMP, so I want to select all the Prices of the value "NAME" and sort it by the oldest Price by using the TIMESTAMP above.

Now I want to make a chart by using microcharts. To create a chart, you have to do something like this:

PriceChart.Chart = new PointChart { Entries = Source };

So I replaced "Source" by PriceList, but thats not going to work.

So how am I supposed to do this...

EDIT: When I use this code:

var singleNameWithOldestPrice = 
    from p in pricePropery
    group p by p.NAME into grp
    select grp.OrderBy(a => a.TIMESTAMP ).First();

How am I supposed to use it as source of the chart, because this is not going to work:

PriceChart.Chart = new PointChart { Entries = singleNameWithOldestPrice };

I cannot convert a List to a source of a PointChart.

Please let me know!

Answer 1

all you want is

var singleNameWithOldestPrice = 
    from p in pricePropery
    group p by p.NAME into grp
    select grp.OrderBy(a => a.TIMESTAMP ).First()