Imports System

Imports System.Linq

Imports System.Collections

Imports System.Collections.Generic

Imports System.Data

Imports System.IO

Imports System.Globalization

Imports System.Reflection

Imports System.ComponentModel.DataAnnotations

Imports System.Xml.Linq

Imports System.Xml

​

Imports Newtonsoft.Json

Imports Newtonsoft.Json.Linq

Imports Newtonsoft.Json.Converters

Imports Newtonsoft.Json.Serialization

​

    ' https://stackoverflow.com/questions/48026549/how-to-retrieve-the-value-of-quotes-in-this-json-format

​

    Public Module TestClass 

​

        Friend Sub Test()

            Dim jsonresp as String = GetJson()

​

            Console.WriteLine("Input JSON: ")

            Console.WriteLine(jsonresp)

​

            Console.WriteLine()

            TestHardcoded(jsonresp)

            Console.WriteLine()

            TestSelectTokens(jsonresp)

​

            Console.WriteLine()

            TestSelectToken(jsonresp)

        End Sub

    Friend Sub TestHardcoded(jsonresp as String)

        Dim quote as Decimal = CType(JToken.Parse(jsonresp).SelectToken("quotes.USDPHP"), Decimal)

        Console.WriteLine("The quote for USDPHP is {0}.", quote)

    End Sub

​

    Friend Sub TestSelectTokens(jsonresp as String)

            ' Extract and deserialize quotes dictionary

            Dim quotes as Dictionary(of String, Decimal) = JToken.Parse(jsonresp) _

                .SelectTokens("quotes") _

                .Select(Function(d) d.ToObject(of Dictionary(of String, Decimal))()) _

                .SingleOrDefault()

​

            ' Show quotes to the user

            Console.WriteLine(If(quotes.Count = 1, "There is 1 quote: ", string.Format("There are {0} quotes", quotes.Count)))

            For Each pair in quotes

                Dim name as String = pair.Key

                Dim quote as Decimal = pair.Value

                Console.WriteLine("   Quote for {0} is {1}.", name, quote)

            Next

            Console.WriteLine("Deserialized and re-serialized dictionary: ")

            Console.WriteLine(JsonConvert.SerializeObject(quotes, Newtonsoft.Json.Formatting.Indented))

        End Sub 

        Friend Sub TestSelectToken(jsonresp as String)

            ' Extract and deserialize quotes dictionary

            Dim quotes as Dictionary(of String, Decimal) = JToken.Parse(jsonresp) _

                .SelectToken("quotes") _

                .ToObject(of Dictionary(of String, Decimal))()

​

            ' Show quotes to the user

            Console.WriteLine(If(quotes.Count = 1, "There is 1 quote: ", string.Format("There are {0} quotes", quotes.Count)))

            For Each pair in quotes

                Dim name as String = pair.Key

                Dim quote as Decimal = pair.Value

                Console.WriteLine("   Quote for {0} is {1}.", name, quote)

            Next

            Console.WriteLine("Deserialized and re-serialized dictionary: ")

            Console.WriteLine(JsonConvert.SerializeObject(quotes, Newtonsoft.Json.Formatting.Indented))

        End Sub 

​

        Function GetJson() as String

Dim Jstring As String = <![CDATA[

{

  "success":true,

  "terms":"https:\/\/currencylayer.com\/terms",

  "privacy":"https:\/\/currencylayer.com\/privacy",

  "timestamp":1514567346,

  "source":"USD",

  "quotes":{

    "USDPHP":49.950001

  }

}

]]>.Value       

        Return Jstring      

        End Function

    End Module

​

    Public Module Module1   

        Public Sub Main()

        Console.WriteLine("Environment version: " & Environment.Version.ToString())

            Console.WriteLine("Json.NET version: " & GetType(JsonSerializer).Assembly.FullName)

            Console.WriteLine("")

​

            Try

​

                TestClass.Test()

​

            Catch ex as Exception

​

                Console.WriteLine("Unhandled exception: ")

                Console.WriteLine(ex)

                Throw

​

            End Try

        End Sub 

    End Module

​

    Public Class AssertionFailedException

        Inherits Exception

        Public Sub New()

        End Sub

        Public Sub New(message As String)

            MyBase.New(message)

        End Sub

        Public Sub New(message As String, inner As Exception)

            MyBase.New(message, inner)

        End Sub

    End Class

    Public Module Assert

        Public Sub IsTrue(value as Boolean, Optional message as String = "failed")

​

            If value = False Then

                Throw New AssertionFailedException(message)

            End If

        End Sub

    End Module