将C＃List转换为JSON特定格式

Question

I have a graph in my view which looks like this:

  var hourlyGraph = Morris.Bar({
            element: 'graph_bar',
            data: [
               @foreach (var item in ViewBag.HourlyGraph)
               {
                @:{device: '@item.Hour.ToString("D2"):00', geekbench:@item.Sales },
               }
            ],
            xkey: 'device',
            ykeys: ['geekbench'],
            labels: ['Sold'],
            barRatio: 0.4,
            barColors: ['#0A4D70', '#34495E', '#ACADAC', '#3498DB'],
            xLabelAngle: 35,
            hideHover: 'auto',
            resize: true
      });

This is a morris chart. Note how the data is set up here:

[
@foreach (var item in ViewBag.HourlyGraph)
{
@:{device: '@item.Hour.ToString("D2"):00', geekbench:@item.Sales },
}
]

And now I need to fill the chart with new data. In my Action I have created a list which contains 2 properties:

public int Hour {get;set;}
public int Sales {get;set;}

And they are stored into a list typed of:

var HourlyGraph = new List<HourlyGraph>();

Now I'd like to convert this list into a JSON format which would look something like this:

[
{device: '0', geekbench:5 },
{device: '1', geekbench:13 },
{device: '2', geekbench:25 },
{device: '3', geekbench:14 },
{device: '4', geekbench:16 },
]

Where value for device would be = hour, and geekbench = sales ...

How could I do this in C#?

Answer 1

With Json.Net and Linq it's easy:

string myJson = 
   JsonConvert.SerializeObject(mylist.Select(item=>
                                  new {device=item.Hour, geekbench=item.Sales}));

You project an anonymous type with the fields and names that you'd like, and let Newtonsoft.Json do the rest.

Answer 2

since you are using mvc why not use return Json() it will convert the object to json string you can use it like

  public ActionResult Myaction()
    { 
        var HourlyGraph = new List<HourlyGraph>();


        return Json(HourlyGraph.Select(x => new {Hour=x.Hour,Sales=x.Sales }));
    }

Answer 3

You can achieve the desired output by using LINQ Anonymous Type

As per example following is class

public class HourlyGraph
{
    public int Hour { get; set; }
    public int Sales { get; set; }
}

Import Namespace System.Web.Script.Serialization which is a Microsoft's Inbuilt Class for dealing with JSON. You will need to refer additional assembly named System.Web.Extensions using 'Add References'.

using System.Web.Script.Serialization;

Declare List and Convert into customized JSON Format

        var listHourlyGraph = new List<HourlyGraph>();

        //Adding some Sample Values
        listHourlyGraph.Add(new HourlyGraph() { Hour = 0, Sales = 5 });
        listHourlyGraph.Add(new HourlyGraph() { Hour = 1, Sales = 10 });

        //Declaring JavaScriptSerialzer Object
        var serialzer = new JavaScriptSerializer();

        //Using Serialize Method which returns back a JSON String
        //We are using LINQ SELECT Method to create a new anonymous return type which contains our custom return types
        string s = serialzer.Serialize(listHourlyGraph.Select(x => new { device = x.Hour, geekbench = x.Sales } ));

You will get the following output in 's' variable

[{"device":0,"geekbench":5},{"device":1,"geekbench":10}]

Note: If you want to get performance optimizations then you are better using Newtonsoft JSON Library instead of Microsoft's Default JSON Library.