DataTable to Json using jquery

Question

I\'m trying to execute a web service which returns a DataTable with the following piece of code:

$.ajax({  
    type: \"POST\",  
    url: url,  
    data: d         


        

Answer 1

It works for very well for me with a WebService

    Imports System.Web.Script.Serialization

    Dim wsServicio As New ["YourWsInstance"]
    Dim dsInstEstado As New DataSet
    Dim sSql As String

    sSql = " Your SQL Statement"
    dsInstEstado = wsServicio.getData("YourWebServiceParameters")
    Dim jsonString = DataTableToJSON(dsInstEstado.Tables("CA_INSTITUCION"))
    Return Json(jsonString, JsonRequestBehavior.AllowGet)

    Function DataTableToJSon(dt As DataTable) As Object
    Dim arr(dt.Rows.Count - 1) As Object
    Dim column As DataColumn
    For i = 0 To dt.Rows.Count - 1
        Dim dict As New Dictionary(Of String, Object)
        For Each column In dt.Columns
            dict.Add(column.ColumnName, dt.Rows(i)(column))
        Next
        arr(i) = dict
    Next
   Return arr
 End Function

Answer 2

I found this C# class very useful:

[Serializable]
public class TableMethod
{
    private int m_total; public int total { get { return this.m_total; } set { this.m_total = value; } }
    private int m_page; public int page { get { return this.m_page; } set { this.m_page = value; } }
    private int m_records; public int records { get { return this.m_records; } set { this.m_records = value; } }
    private IList<RowElement> m_rows; public IList<RowElement> rows { get { return this.m_rows; } set { this.m_rows = value; } }
    public TableMethod()
    {
        this.m_records = 20;
        this.m_total = 20;
        this.m_page = 1;
    }
}
[Serializable]
public class RowElement
{
    public string id;
    public string[] cell;
}

Answer 3

Like Marc, I too am not surprised that the DataTable breaks your webservice/json exchange. I'd like to endorse Json.NET also.

But if you decide to not go with it, you still don't have to build the json manually. Just make your own lean custom class with all the properties you need and then return an array of that class. You will of course have to write code to "convert" your data table into your new class. I know, it could be a lot of code writing, but it's a lot less error prone then trying to manually make a json string.