Ajax VB Json string - asp.net

Question

I am having difficulties finding a Visual Basic Json string that will work for this instance. I keep getting an "Error Message Status" of "[ object Object ]".
I got this same one to work in C# with "\"" in the Json code but VB is not so easy.
Default.aspx
<script type="text/javascript" src="~/jquery=1.10.2.js"></script>
<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<script type="text/javascript">
$(document).ready(function () {
$("#<%= Button1.ClientID %>").click(function () {
var mo1 = $("#<%= TextBox1.ClientID %>").val();
var dy1 = $("#<%= TextBox2.ClientID %>").val();
var yr1 = $("#<%= TextBox3.ClientID %>").val();
var data = { mo: mo1, dy: dy1, yr: yr1 };
var json1 = JSON.stringify(data);
$.ajax
({
type: "POST",
contentType: "application/json; charset=utf-8",
dataType: "json",
data: json1,
url: "Default.aspx/GetDate",
success: function (result) {
$("#<%= TextBox4.ClientID %>").val(result.d);
$("#<%= Button2.ClientID %>").trigger(click);
},
error: function (status, ex) {
alert("Error Code: Status: " + status + " Ex: " + ex);
}
});
return false;
});
});
</script>
Default.aspx.vb
<System.Web.Services.WebMethod> Public Shared Function GetDate(ByVal mo As Integer, ByVal dy As Integer, ByVal yr As Integer) As String
...
json1 = "[{""id"":""100"",""datetime"":""04/10/2017"",""col1"":""1"",""col2"":""2"",""col3"":""3""}]"
Dim jsonout As String = JsonConvert.SerializeObject(json1)
Return jsonout
End Function
I tried others:
'json1 = "[{" & Chr(34) & "id" & Chr(34) & ":" & Chr(34) & dataa(i, 1) & Chr(34) & "," & Chr(34) & "datetime" & Chr(34) & ":" & Chr(34) & dataa(i, 2) & Chr(34) & "," & Chr(34) & "col1" & Chr(34) & ":" & Chr(34) & dataa(i, 3) & Chr(34) & "," & Chr(34) & "col2" & Chr(34) & ":" & Chr(34) & dataa(i, 4) & Chr(34) & "," & Chr(34) & "col3" & Chr(34) & ":" & Chr(34) & dataa(i, 5) & Chr(34) & "}]"
'json1 = "[{""id"":""" & dataa(i, 1) & """,""datetime"":""" & dataa(i, 2) & """,""col1"":""" & dataa(i, 3) & """,""col2"":""" & dataa(i, 4) & """col3"","":""" & dataa(i, 5) & """}]"
'json1 = "[{" & """id"":"" & dataa(i, 1) & "",""datetime"":"" & dataa(i, 2) & ""col1"":"" & dataa(i, 3) & "",""col2"":"" & dataa(i, 4) & "",""col3"":"" & dataa(i, 5) & ""}]"
'json1 = "[{" & """id""" & ":""" & dataa(i, 1) & """," & """datetime""" & ":""" & dataa(i, 2) & """," & """col1""" & ":""" & dataa(i, 3) & """," & """col2""" & ":""" & dataa(i, 4) & """," & """col3""" & ":""" & dataa(i, 5) & """}]"
'json1 = "[{" & """ & "id" & """ & ":" & """ & "100" & """ & "," & """ & "datetime" & """ & ":" & """ & "04/10/2017" & """ & "," & """ & "col1" & """ & ":" & """ & "1" & """ & "," & """ & "col2" & """ & ":" & """ & "2" & """ & "," & """ & "col3" & """ & ":" & """ & "3" & """ & "}]"
Class.vb
Public Class datapart
Public Property id() As Integer
Get
Return m_id
End Get
Set(value As Integer)
m_id = value
End Set
End Property
Private m_id As Integer
Public Property datetime() As String
Get
Return m_datetime
End Get
Set(value As String)
m_datetime = value
End Set
End Property
Private m_datetime As String
Public Property col1() As Integer
Get
Return m_col1
End Get
Set(value As Integer)
m_col1 = value
End Set
End Property
Private m_col1 As Integer
Public Property col2() As Integer
Get
Return m_col2
End Get
Set(value As Integer)
m_col2 = value
End Set
End Property
Private m_col2 As Integer
Public Property col3() As Integer
Get
Return m_col3
End Get
Set(value As Integer)
m_col3 = value
End Set
End Property
Private m_col3 As Integer
End Class