Hello all,

I think this should be a simple issue but I am having nothing but trouble.  My code currently passes a system.object containing an array of paramaters to a web service.  The WS then takes thes parameters and calls a stored procedure and returns a dataset to the calling web form.  I have converted a former class into a web service with no luck.  If I put the .vb file in the app_code folder it works fine, if I add it as a web reference from another location I get an error stating that there was an error creating the XML file. 

Here is the calling code:

Dim clsGN as new Service
Dim ds as new DataSet
Dim arParams(0) as object

ds = clsGN.GetData("spName", arParms)

WS Code:

 <WebMethod(MessageName:="GetData", Description:="gets dataset with parameters")> _
    Public Function GetData(ByVal SPName As String, ByVal SPVals As Object) As DataSet

        Dim oDS As New DataSet
        Dim oDSVals As New DataSet
        Dim adapter As SqlDataAdapter
        Dim conn As SqlConnection
        Dim comm As SqlCommand


        'Get the paramater value types from the stored procedure
        oDSVals = GetSPValueTypes(SPName)

        'Initialize connection
        conn = New SqlConnection(connectionString)

        'Create Command
        comm = New SqlCommand(SPName, conn)
        comm.CommandType = CommandType.StoredProcedure

        Dim x As Integer = 0

        For x = 0 To SPVals.GetUpperBound(0)

            Dim sType As New SqlDbType
            Dim sParamName As String = String.Empty
            'Get the SQL parameter data type from oDSVals to attach to the command parameters
            sType = AssignSQLParameterType(oDSVals.Tables(0).Rows(x).Item("data_type"))
            sParamName = oDSVals.Tables(0).Rows(x).Item("parameter_name")

            comm.Parameters.Add(sParamName, sType)
            comm.Parameters(sParamName).Value = SPVals(x)
        Next

        'Create adapter
        adapter = New SqlDataAdapter(comm)

        'Fill the dataset
        adapter.Fill(oDS)

        'Close the connection
        conn.Close()
        conn.Dispose()
        comm.Dispose()
        oDSVals.Dispose()

        Return oDS

    End Function 

Thanks for your help.

You will need a custom converter / parser to serialize the dataset, it is not a normal function of a web service. There are other options such as returning straight up XML, but you won't be able to return an actual DataSet without some extra coding involved. 

A dataset can be returned by a Web Service e.g.

    /// <summary>
    /// Gets the event log dataset.
    /// </summary>
    /// <returns>Dataset of Event Log Entries</returns>
    [WebMethod(Description = "Gets the event log dataset")]
    public DataSet GetEventLogDataset()
    {
      return CommonData.GetEventLogDataSet;
    }

This is from CommonService.asmx in the CommonWebService project in the CommonData solution at http://commondata.codeplex.com/