Generate JSON string with nested (child) data using C# and VB.Net in ASP.Net

Hi ruben00000,

You need to use JavaScriptSerializer class to get the JSON string.

Please refer below sample.

HTML

<asp:Label ID="lblJson" runat="server" />

Namespace

C#

using System.Web.Script.Serialization;

VB.Net

Imports System.Web.Script.Serialization

Code

C#

protected void Page_Load(object sender, EventArgs e)
{
    if (!this.IsPostBack)
    {
        List<SubResult> subResults = new List<SubResult>() 
        {
            new SubResult() { RId = 1, Company="valid", Type="invalid"},
            new SubResult() { RId = 2, Company="valid", Type="valid"}
        };

        List<Result> results = new List<Result>() 
        {
            new Result() { Id = 1, Company="DEFGA", Type="Null" },
            new Result() { Id = 2, Company="DEFGC", Type="Test" }
        };

        foreach (Result result in results)
        {
            List<SubResult> sr = new List<SubResult>();
            foreach (SubResult subResult in subResults)
            {
                if (subResult.RId == result.Id)
                {
                    sr.Add(subResult);
                }
            }

            result.Checking = sr;
        }

        BaseJsonResponseUploadBulk rs = new BaseJsonResponseUploadBulk()
        {
            code = "1",
            message = "success",
            result = results
        };

        lblJson.Text = new JavaScriptSerializer().Serialize(rs);
    }
}

public class BaseJsonResponseUploadBulk
{
    public object code { set; get; }
    public object message { set; get; }
    public List<Result> result { get; set; }
}

public class Result
{
    [ScriptIgnore]
    public int Id { get; set; }
    public string Company { get; set; }
    public string Type { get; set; }
    public List<SubResult> Checking { get; set; }
}

public class SubResult
{
    [ScriptIgnore]
    public int RId { get; set; }
    public string Company { get; set; }
    public string Type { get; set; }
}

VB.Net

Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs) Handles Me.Load
    If Not Me.IsPostBack Then
        Dim subResults As List(Of SubResult) = New List(Of SubResult)() From {
            New SubResult() With {
                .RId = 1,
                .Company = "valid",
                .Type = "invalid"
            },
            New SubResult() With {
                .RId = 2,
                .Company = "valid",
                .Type = "valid"
            }
        }
        Dim results As List(Of Result) = New List(Of Result)() From {
            New Result() With {
                .Id = 1,
                .Company = "DEFGA",
                .Type = "Null"
            },
            New Result() With {
                .Id = 2,
                .Company = "DEFGC",
                .Type = "Test"
            }
        }

        For Each result As Result In results
            Dim sr As List(Of SubResult) = New List(Of SubResult)()
            For Each subResult As SubResult In subResults
                If subResult.RId = result.Id Then
                    sr.Add(subResult)
                End If
            Next
            result.Checking = sr
        Next
        Dim rs As BaseJsonResponseUploadBulk = New BaseJsonResponseUploadBulk() With {
            .code = "1",
            .message = "success",
            .result = results
        }
        lblJson.Text = New JavaScriptSerializer().Serialize(rs)
    End If
End Sub

Public Class BaseJsonResponseUploadBulk
    Public Property code As Object
    Public Property message As Object
    Public Property result As List(Of Result)
End Class

Public Class Result
    <ScriptIgnore()>
    Public Property Id As Integer
    Public Property Company As String
    Public Property Type As String
    Public Property Checking As List(Of SubResult)
End Class

Public Class SubResult
    <ScriptIgnore()>
    Public Property RId As Integer
    Public Property Company As String
    Public Property Type As String
End Class

Screenshot