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.netasp.netvb.netjson.net-3.5

How to create JSON data with .NET?


At the moment, I am building json data as follows:

<%@ Page Language="VB" Debug="True" EnableViewState="false" %>

<%@ Import Namespace="System.Data" %>
<%@ Import Namespace="System.Data.SqlClient" %>
<%@ Import Namespace="System.IO" %>

<script runat="server">
    Dim objSQLConnection As SqlConnection
    Dim objSQLCommand As SqlCommand
    Dim objSQLDataReader As SqlDataReader
    Dim objJSONStringBuilder As StringBuilder

    Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs)
        Response.Clear()
        Response.ContentType = "application/json"
        Response.Write(get_json())
        Response.End()
    End Sub

    Function get_json() As String
        objJSONStringBuilder = New StringBuilder()
        objSQLConnection = New SqlConnection(System.Configuration.ConfigurationManager.AppSettings("connString"))

        objSQLCommand = New SqlCommand("sql query goes here", objSQLConnection)

        objJSONStringBuilder.Append("[")

        objSQLCommand.Connection.Open()
        objSQLDataReader = objSQLCommand.ExecuteReader()

        While objSQLDataReader.Read()
            objJSONStringBuilder.Append("{")
            objJSONStringBuilder.Append("""col1""")
            objJSONStringBuilder.Append(":")
            objJSONStringBuilder.Append("""" & objSQLDataReader("col1") & """")
            objJSONStringBuilder.Append(",")
            objJSONStringBuilder.Append("""col2""")
            objJSONStringBuilder.Append(":")
            objJSONStringBuilder.Append("""" & objSQLDataReader("col2") & """")
            objJSONStringBuilder.Append(",")
            objJSONStringBuilder.Append("""col3""")
            objJSONStringBuilder.Append(":")
            objJSONStringBuilder.Append("""" & objSQLDataReader("col3") & """")
            objJSONStringBuilder.Append("},")
        End While

        objSQLDataReader.Close()
        objSQLCommand.Connection.Close()

        objJSONStringBuilder.Remove(objJSONStringBuilder.Length - 1, 1)

        objJSONStringBuilder.Append("]")

        Return objJSONStringBuilder.ToString
    End Function
</script>

Is this the preferred method of creating JSON data using .NET?

I think I am supposed to use asmx web services with arrays converted to json? But all the examples I have seen are in C#.


Solution

  • Normally, with ASP.NET, you shouldn't be doing anything to serialize to JSON. Just make your request with the correct type, return it correctly, and ASP.NET will serialize to JSON for you. It can also deserialize.