Migrate Web Services (VS2003) to WCF (VS2010) - ajax

Question

Our site is maintained with VS2003. We converted our solution to VS2010--it is a Web Application Project. It has several Web Services files (.asmx file endings) that we hoped to convert to WCF in two stages, first preserve the function of the asmx files that write back XML documents via AJAX to the client..., and then learn to build AJAX-enabled WCF Services to do the same things.
We have researched the 'Could not create type xxx'-error and the advice varies. We're certain(!!) that having an App_Code folder is not the difference, and that we've named our namespace and class correctly, and that we've decorated the Web Service code correctly, and that we're able to use ASP.Net 2.0 to activate these services, and that we have the application level set correctly in IIS... and we're still not able to get past the error.
Here is our asmx code (we created a test page with ScriptManager control to try to hit this one Web Method, but we never got past the build for the service). You certainly don't need to bother with the actual database pulls, but I left them in anyway:
Imports System
Imports System.Web
Imports System.Web.Services
Imports System.Web.Services.Protocols
Imports System.Web.Script.Services
Imports System.ComponentModel
Imports System.Data.SqlClient
Imports System.Text
Imports System.Uri
Imports System.Xml
Imports System.IO
<WebService([Namespace]:="nsCarousel", Description:="Carousel Web Service Methods")> _
<WebServiceBinding(ConformsTo:=WsiProfiles.BasicProfile1_1)> _
<System.Web.Script.Services.ScriptService()> _
Public Class Carousel
Inherits WebService
<WebMethod(Description:="Get Dealer Info")> _
Public Function GetDealerInfo(ByVal DID%) As String
Dim s$, sql$, sRequest$, sRequestPathQuery$, sDID$, sAJAX$, sReturn$, sIP$, sWebSite$, sErr$, sDealerSearch$
Dim sXML$, sXMLDealerResults$, sXMLPath$
Dim sUserName$, sGeneralDesc$, sStatusText$
Dim bPost As Boolean
Dim bHaveData As Boolean
Dim ds As DataSet
Dim dasql As SqlDataAdapter
Dim sqldr As SqlDataReader
Dim sqlConn As SqlConnection
Dim sqlCmd As SqlCommand
Dim xdoc As New XmlDocument
Dim xnode As XmlNode
Dim xrefnode As XmlNode
Dim xnewnode As XmlElement
Try
'/ need test of sRequest for reference and use in test just below
bPost = False
sDID = Convert.ToString(DID)
sGeneralDesc = "Dealer Pull"
sqlConn = New SqlConnection(ConfigurationSettings.AppSettings("ConnectionStringLong"))
sqlConn.Open()
'/ new sp to preserve nodes, even when fields are null
'/ get results for individual dealer
sql = "insert into junk(entrydate, sql_stmts) select GetDate(), '" & sDID & "';"
sqlCmd = New SqlCommand(sql, sqlConn)
sqlCmd.ExecuteNonQuery()
sqlCmd.Dispose()
sql = "Select_DRPROByDID_xml " & sDID
sqlCmd = New SqlCommand(sql, sqlConn)
sqldr = sqlCmd.ExecuteReader()
'/ quick test if have data
bHaveData = False
Do While sqldr.Read
If Not (IsDBNull(sqldr("DNum"))) Then
bHaveData = True
End If
Exit Do
Loop
sqldr.Close()
sqldr = Nothing
sqlCmd.Dispose()
sqlCmd = Nothing
'/ s will include a node for NewDataSet -> remove and add nodes for msg based on status
'/ and DealerError
If bHaveData Then
dasql = New SqlDataAdapter(sql, sqlConn)
ds = New DataSet
dasql.Fill(ds)
s = ds.GetXml
sXMLDealerResults = s
dasql.Dispose()
ds.Clear()
dasql = Nothing
ds = Nothing
'/ query the XML doc
xdoc.LoadXml(s)
xnode = xdoc.SelectSingleNode("/NewDataSet/Table")
If (xnode.HasChildNodes) Then
If (sDID.Length > 0) Then
sStatusText = xdoc.GetElementsByTagName("DRStat").Item(0).InnerText
Select Case sStatusText
Case "A"
'/ test next when opportunity exists
'/ set current node at Table
'sXMLPath = "/NewDataSet/Table"
'/ set Table as the current node
'xrefnode = xdoc.SelectSingleNode(sXMLPath)
'xnewnode = xdoc.CreateElement("DealerMsg")
'sStatusText = "Active dealer found."
'xdoc.InsertAfter(xnewnode, xrefnode)
sXMLDealerResults = sXMLDealerResults.Replace("<Table>", "<Table><DealerMsg>Active dealer found.</DealerMsg>")
Case "C"
sXMLDealerResults = sXMLDealerResults.Replace("<Table>", "<Table><DealerMsg>Dealer has been cancelled.</DealerMsg>")
Case "H"
sXMLDealerResults = sXMLDealerResults.Replace("<Table>", "<Table><DealerMsg>Dealer is on hold.</DealerMsg>")
Case Else
sXMLDealerResults = sXMLDealerResults.Replace("<Table>", "<Table><DealerMsg>Dealer status is invalid.</DealerMsg>")
End Select
sXMLDealerResults = sXMLDealerResults.Replace("<Table>", "<Table><DealerError>1</DealerError>")
Else
'/ do nothing
End If
Else
sXMLDealerResults = sXMLDealerResults.Replace("<Table>", "<Table><DealerError>0</DealerError><DealerMsg>Dealer not found.</DealerMsg>")
End If
Else
sXMLDealerResults = "<Table><DealerError>0</DealerError><DealerMsg>Dealer not found.</DealerMsg></Table>"
End If
sXMLDealerResults = sXMLDealerResults.Replace("<NewDataSet>", "")
sXMLDealerResults = sXMLDealerResults.Replace("</NewDataSet>", "")
If (sDID.Length > 0) Then
sXMLDealerResults = sXMLDealerResults.Replace("<Table>", "")
sXMLDealerResults = sXMLDealerResults.Replace("</Table>", "")
Else
sXMLDealerResults = sXMLDealerResults.Replace("<Table>", "<Dealer>")
sXMLDealerResults = sXMLDealerResults.Replace("</Table>", "</Dealer>")
End If
sXML = "<?xml version=""1.0"" ?><DealerFetch>" + sXMLDealerResults.Trim + "</DealerFetch>"
'If sReturn.Trim.Length = 0 Then
' Response.ContentType = "text/xml"
' Response.Write(sXML)
'End If
sqlConn.Close()
sqlConn = Nothing
Return sXML
Catch exp As Exception
sErr = sErr & " " & exp.Message.ToString
End Try
End Function
End Class
Any help would be appreciated. Maybe it's something obvious that will appear to someone here quickly, but it sure is making us fret!!! If you need more info or code, please let us know.

Answer 1

There are tons of good samples and demos how to achieve this.......
Just a few a quick Google search turned up:
Convert existing asmx .net web service to WCF service in .net 3.0/3.5
Convert .asmx file to WCF .svc file to create simple API web service
Migrating a Versionable ASMX Web Service to WCF
I would just search Google for your keywords (ASMX, WCF, Migrate) and you should get tons of links and useful resources.....
As for resources to learn the basics of WCF: there's the MSDN WCF Developer Center which has everything from beginner's tutorials to articles and sample code.
Also, check out the screen cast library up on MSDN for some really useful, 10-15 minute chunks of information on just about any topic related to WCF you might be interested in.