将JSON转换为VB.NET数据表的问题

Question

following is me JSON response text. I validated response and there is no error. I am trying to convert it to data table but it gives me null or error.

JSON Response:

    {
  "data": {
    "b2b": [
      {
        "inv": [
          {
            "itms": [
              {
                "num": 1,
                "itc": {
                  "tx_cs": 0,
                  "elg": "ip",
                  "tx_i": 180
                },
                "itm_det": {
                  "csamt": 0,
                  "rt": 18,
                  "txval": 1000,
                  "iamt": 180
                }
              }
            ],
            "val": 1000,
            "inv_typ": "R",
            "flag": "N",
            "updby": "S",
            "pos": "27",
            "idt": "24-07-2017",
            "rchrg": "N",
            "cflag": "U",
            "inum": "191001",
            "chksum": "52d0e920428464d85721bfcd7f3bfb4f16fd00d93a9df7d6a6f0814bed716c28"
          },
          {
            "itms": [
              {
                "num": 1,
                "itc": {
                  "tx_cs": 0,
                  "elg": "ip",
                  "tx_i": 18
                },
                "itm_det": {
                  "csamt": 0,
                  "rt": 18,
                  "txval": 100,
                  "iamt": 18
                }
              }
            ],
            "val": 100,
            "inv_typ": "R",
            "flag": "N",
            "updby": "S",
            "pos": "27",
            "idt": "24-07-2017",
            "rchrg": "N",
            "cflag": "U",
            "inum": "191002",
            "chksum": "aaa1efcf335549b58059c9f3d03807d7c41b007022216f8a90db12c60cd2b9ef"
          }
        ],
        "cfs": "N",
        "ctin": "1225586"
      }
    ]
  },
  "header": {
    "email": "test@test.com",
    "gstin": "65656451",
    "retperiod": "072017",
    "gst_username": "sampleaccount",
    "state_cd": "27",
    "ip_address": "192.168.2.200",
    "txn": "s4f5sdf54sdf5s4df5",
    "client_id": "removedfortest",
    "client_secret": "removedfortest",
    "authorization": "Basic a4s5df45asdf54as5d4f",
    "ret_period": "072017"
  },
  "status_cd": "1",
  "status_desc": "request succeeds"
}

---

Following are the classes i defined

Public Class Itc
        Public Property tx_cs As Integer
        Public Property elg As String
        Public Property tx_i As Integer
    End Class

    Public Class ItmDet
        Public Property csamt As Integer
        Public Property rt As Integer
        Public Property txval As Integer
        Public Property iamt As Integer
    End Class

    Public Class Itm
        Public Property num As Integer
        Public Property itc As Itc
        Public Property itm_det As ItmDet
    End Class

    Public Class Inv
        Public Property itms As Itm()
        Public Property val As Integer
        Public Property inv_typ As String
        Public Property flag As String
        Public Property updby As String
        Public Property pos As String
        Public Property idt As String
        Public Property rchrg As String
        Public Property cflag As String
        Public Property inum As String
        Public Property chksum As String
    End Class

    Public Class B2b
        Public Property inv As Inv()
        Public Property cfs As String
        Public Property ctin As String
    End Class

    Public Class Data
        Public Property b2b As B2b()
    End Class

    Public Class Header
        Public Property email As String
        Public Property gstin As String
        Public Property retperiod As String
        Public Property gst_username As String
        Public Property state_cd As String
        Public Property ip_address As String
        Public Property txn As String
        Public Property client_id As String
        Public Property client_secret As String
        Public Property authorization As String
        Public Property ret_period As String
    End Class

    Public Class Example
        Public Property data As Data
        Public Property status_cd As String
        Public Property status_desc As String
        Public Property header As Header
    End Class

---

and then i am trying to do following:

Following return me Null in datatable

Dim table as datatable = JsonConvert.DeserializeObject(Of RootObject(Of DataTable))(responsetext).Table

also tried: following does not allow me to type in rootofTable.data

    Dim rootOfList = JsonConvert.DeserializeObject(Of RootObject(Of List(Of data)))(responsetext)
Dim table As DataTable = rootOfTable.data

None of these are returning me values to datatable. Dataset stay null.

This is what i want

Please help to resolve.

Thanks

Answer 1

There are at least 4 different ways it could be done (that I can think of) here is one example, I think it should be enough for you.

You basically just set which part of json goes into what column.

Imports Newtonsoft.Json.Linq

Public Class Form1

Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
    Dim JsonP As JObject = JObject.Parse(TextBox1.Text)
    Dim SetPointer As JToken = JsonP("data")("b2b")(0)("inv")

    For Each item In SetPointer
        Dim NewDR As DataRow = TempDT.NewRow
        NewDR("val") = item("val")
        NewDR("inv_typ") = item("val")
        NewDR("flag") = item("flag")
        NewDR("updby") = item("updby")
        NewDR("pos") = item("pos")
        NewDR("idt") = item("idt")
        NewDR("rchrg") = item("rchrg")
        NewDR("cflag") = item("cflag")
        NewDR("inum") = item("inum")
        NewDR("chksum") = item("chksum")
        NewDR("itms_num") = item("itms")(0)("num")
        NewDR("itms_itc_cs") = item("itms")(0)("itc")("tx_cs")
        TempDT.Rows.Add(NewDR)
    Next
    DataGridView1.DataSource = TempDT
End Sub

Dim TempDT As New DataTable
Private Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click
    TempDT.Columns.Add("val")
    TempDT.Columns.Add("inv_typ")
    TempDT.Columns.Add("flag")
    TempDT.Columns.Add("updby")
    TempDT.Columns.Add("pos")
    TempDT.Columns.Add("idt")
    TempDT.Columns.Add("rchrg")
    TempDT.Columns.Add("cflag")
    TempDT.Columns.Add("inum")
    TempDT.Columns.Add("chksum")
    TempDT.Columns.Add("itms_num")
    TempDT.Columns.Add("itms_itc_cs")
End Sub
End Class

I didn't do everything, it's simply a demonstration of concept.

---

Use json visualizer. https://jsonformatter.curiousconcept.com/ then as you navigate trough it you write out the name if it's {}, number if it's an array [] .

Like you can totally write out ("data")("b2b")(0)("inv")(0)("itms")(0)("itc")("tx_cs") to get value from it. But it would be easier to navigate to somewhere closer and then just write a part of it like ("itms").

And you can't write a fixed path for arrays most of the time as they have dynamic amount of members most of the time, so instead of (0) you will have to do (x) and loop over items.