Imports System

Imports System.Collections.Generic

Imports Newtonsoft.Json

Imports Newtonsoft.Json.Linq

Public Module Module1

    Public Sub Main()

        Dim d As New Dictionary(Of String, String)

        d.Add("test.nested", "value")

        d.Add("test.nested2", "value2")

        d.Add("test.nested3.moreNested.evenMoreNested", "value3")

        Dim output As String = JsonHelper.DictionaryToJson(d)

        Console.WriteLine(output)

    End Sub

​

    Class JsonHelper

        Public Shared Function DictionaryToJson(dict As Dictionary(Of String, String)) As String

            Dim root As New JObject()

            For Each kvp As KeyValuePair(Of String, String) In dict

                FindOrAdd(root, kvp.Key, kvp.Value)

            Next

            Return root.ToString()

        End Function

​

        Private Shared Function FindOrAdd(parent As JObject, key As String, value As String) As JObject

        If key Is Nothing Then Return parent

            Dim i As Integer = key.IndexOf(".")

            If i > -1 Then

                Dim obj As JObject = FindOrAdd(parent, key.Substring(0, i), Nothing)

                Return FindOrAdd(obj, key.Substring(i + 1), value)

            End If

            Dim prop As JProperty = parent.Property(key)

            If value Is Nothing Then

                Dim child As JObject

                If prop Is Nothing Then

                    child = New JObject()

                    parent.Add(key, child)

                Else If prop.Value.Type = JTokenType.Object

                    child = DirectCast(prop.Value, JObject)

                Else

                    Throw New JsonException("The key """ + parent.Path + "." + key + """ already has a value of """ + prop.Value.ToString() + """.")

                End If

                Return child

            Else

                If prop Is Nothing Then

                    parent.Add(key, New JValue(value))

                    Return parent

                Else

                    Throw New JsonException("The key """ + parent.Path + "." + key + """ already has a value of """ + prop.Value.ToString() + """.")

                End If

            End If

        End Function

    End Class

​

End Module