What type to use for an array of JSON objects?

Question

I have a WCF service that receives a JSON payload.

For instance, a payload like this:

{ "a":"123", "b":"xyz" }

Works well with the following service method signature:

<OperationContract()>
Public Sub SomeMethod(ByVal a As Integer, ByVal b As String)

a and b are automatically casted to an Integer and a String respectively.

However, now I need to send a slightly more complex argument to the service method, one that isn't an Integer or a String:

{ "a":"123", "b":"xyz", "c":"[ { "key":"1", "val":"2" }, { "key":"2", "val":"3" } ]" }

Basically, c is an array of objects containing key-value pairs (i.e. JSON objects). So, what type do I declare c as in the service method signature? I'm not really familiar with VB, so I don't know what types are available. If possible, please also include an example of how to get the values out of whatever type you suggest.

Answer 1

I use System.Collections.ArrayList for this and you can then iterate through it using a For Each.

I don't know what you are using to deserialize your JSON but I use JavaScriptSerializer, E.g...

Imports System.Collections
Imports System.Collections.Generic
Imports System.Web.Script.Serialization

and then...

Dim sJSON as String = "{}" 'Contains the JSON in your question
Dim jsSerializer As JavaScriptSerializer = New JavaScriptSerializer()

Dim dictData As Dictionary(Of String, Object) = jsSerializer.Deserialize(Of Dictionary(Of String, Object))(sJSON)

If dictData.ContainsKey("c") Then
    If TypeOf dictData("c") Is ArrayList Then
        Dim arrData As ArrayList = DirectCast(dictData("c"), ArrayList)
        For Each arrDataRecord In arrData
        Next
    End If
End If