Question

So at Im trying to make a CMS system that utilizies the yahoo messenger SDK. THe idea is to have a self help robot be able to guide clients through certain problems. The conversation is run by two methods. One a script exists to respond back with a generic response. In each message recieved by the client the program will look for certan keywords and questions that will trigger a response out of an XML file. If it dosent find one it continues with the script. The program works but at a cost. Its a huge resource hog. In the program I have a class that handles all of the yahoo messenger functions like login, logout, recieve and send messages. I also have a class that I call conversations. This keeps rack of where the message came form, who it was going to and what position it was in within the scripted conversation. In my main program i initilize X amount of the client class based on how many different sites help accouts I am using. Each time it recieves a message it either creates a new conversation class because it dosent exist or it checks for the existing conversation and finds the sripted position. It obviously does all of the checks for keywords on the incoming message as well. This is my code for the shared event handler for recieving messages. My question is, is there anywayto make this more efficient.

    Private Sub yahooclients_OnRec(ByVal sender As Object, ByVal buddy As String, ByVal message As String)
    TotalRec = TotalRec + 1

    Try


        Dim c As YahooClient = CType(sender, YahooClient) 'Yahoo Client To Send Message From 
        showLog("From:" & buddy & " To:" & c.Account & " Message:" & message)
        Dim msgSplit As String()
        Dim retmsg As String
        Dim smsg As String()
        Dim n1 As XmlNode
        Dim sran As New Random 'Random SPlit Message
        Dim domran As New Random 'Random Domain ID
        Dim Found1 As Boolean = False
        Dim FoundIt As Integer = 0
        Dim i As Integer = 0 'Keyword Counter
        'Check Message For KeyWords By Splitting Each phrase by spaces
        msgSplit = Split(message, " ")
        For Each word In msgSplit
            For Each value In KeywordInd
                If value = word Then
                    n1 = m_nodelist.Item(i)
                    retmsg = n1.InnerText
                    GoTo ScrubMessage
                End If
                i = i + 1
            Next
            i = 0
        Next

        'Check For Conversations
        If convos.Count = 0 Then
            convos.Add(New Conversation(c.Account, buddy, 0))
            retmsg = Script(0)
            GoTo ScrubMessage
        Else
            For A As Integer = 0 To (convos.Count - 1)
                If InStr(convos(A).TUser, c.Account) > 0 And InStr(convos(A).FUser, buddy) > 0 Then
                    Found1 = True
                    Exit For
                End If
                FoundIt = FoundIt + 1
            Next
            If Found1 = True Then
                convos(FoundIt).SPosition = convos(FoundIt).SPosition + 1
                'Send Next Position In Script
                If convos(FoundIt).SPosition > (Script.Length - 1) Then
                    If convos(FoundIt).SPosition = Script.Length Then
                        TotalScript = TotalScript + 1
                        ToolStripStatusLabel10.Text = TotalScript
                    End If
                    Exit Sub
                End If
                retmsg = Script(convos(FoundIt).SPosition)
                GoTo ScrubMessage
            Else
                convos.Add(New Conversation(c.Account, buddy, 0))
                retmsg = Script(0)
                GoTo ScrubMessage
            End If
        End If

ScrubMessage:
‘Strip out |
smsg = Split(retmsg, “|”)

        'Pull A Random Response
        If smsg.Length > 1 Then
            retmsg = smsg(sran.Next(0, (smsg.Length) - 1))
        Else
            retmsg = smsg(0)
        End If


        'Check For Domain Indicator
        If InStr(retmsg, "%") > 0 Then
            TotalLink = TotalLink + 1
        End If
        retmsg = Replace(retmsg, "%s", Domains(domran.Next(0, (Domains.Length - 1))))

        If CheckBox2.Checked = True Then 'send Message With Font and Color
            retmsg = "<font face=" & """" & fname & """" & ">" & "[#FF80C0m" & retmsg & "</font>"
        End If


        showLog(("Sending Message: " & retmsg & " To: " & buddy & " From: " & c.Account))
        c.SendMessage(buddy, retmsg)
        TotalSent = TotalSent + 1
        ToolStripStatusLabel4.Text = TotalSent 'Updates Sent Counter
        ToolStripStatusLabel6.Text = TotalRec 'Updates Rec Counter
        ToolStripStatusLabel8.Text = TotalLink 'Updates Links counter

    Catch ex As Exception
        showLog(ex.ToString)
    End Try

End Sub

The program becomes really no resonsive with alot of accounts are asking questions etc.

Answer 1

There are few things that look like a good place to start.

1) Pull the code after ScrubMessage into it’s own function which takes the needed information as parameters. Then replace all the GoTos with calls. This probably will not improve performance, but makes the code easier for most people to understand (and convention says raw gotos are evil).

Sub ScrubAndSendMessage(response As String, client As YahooClient)
    'code after label here with needed local variables
End Sub

2) You are searching through a list for every word of every incoming message. Based on the usage, KeywordInd and m_nodelist are probably declared something like this:

Dim KeywordInd As List(Of String)
Dim m_nodelist As List(Of XmlNode) 'or whatever type has the inner text

Since the keyword list seems to be a key into the node list of values, I would suggest using a dictionary to simplify the code and potentially improve speed.

Dim wordResponse As New Dictionary(Of String, String)

where the keys are the words from KeywordInd and the values are the InnerText from m_nodelist which lets you say

For Each word In msgSplit
    If wordResponse.ContainsKey(word) Then
        ScrubMessage(wordResponse(word))
        Exit Sub
    End If
Next

3) Try associating the conversation directly with the YahooClient object so you do not have to do the lookup every time to find the conversation. When you do that, you can also make sure that there is a Conversation associated with every client if desired.

4) You are interacting directly with what look to be UI components in the handler. This requires that all handlers for all clients run on the UI thread. You would probably be better of raising some events from this handler and letting the form handle the events and post across to the UI thread as needed. The events would probably be ScriptPositionAdvanced and ResponseSent or something similar. The form/control could then handle these events and post to the UI thread according to the pattern used by your UI framework of choice, which you should be able to find with a quick search.