get a field value from a webpage - lotusscript

问题

I need to read the field value from a webpage using lotusscript. Essentially I am planning on writing an agent to go to a specific URL, get a value from the page, and then use this value for the url it sends the user to.

Can anyone give me a pointer?

A

回答1:

I do this all the time, it is not hard at all (on Windows). I created a class to do this, so it is very easy to implement.

Here is how you call it:

Dim internet As New RemoteHTML()
Dim html As String
html = internet.GetHTTP("http://www.texasswede.com/mypage.html")

That's it, now you just pull whatever information you want out of the html string.

Here is the class:

Option Public
Option Declare

Class RemoteHTML
    Private httpObject As Variant
    Public httpStatus As Integer

    Public Sub New()
        Set httpObject = CreateObject("MSXML2.ServerXMLHTTP")
    End Sub

    Public Function GetHTTP(httpURL As String) As String
        Dim retries As Integer
        retries = 0     
        Do
            If retries>1 Then
                Sleep 1     ' After the two first calls, introduce a 1 second delay betwen each additional call
            End If
            retries = retries + 1   
            Call httpObject.open("GET", httpURL, False)
            Call httpObject.send()
            httpStatus = httpObject.Status
            If retries >= 10 Then
                httpStatus = 0  ' Timeout
            End If
        Loop Until httpStatus = 200 Or httpStatus > 500 Or httpStatus = 404  Or httpStatus = 0
        If httpStatus = 200 Then
            GetHTTP = Left$(httpObject.responseText,16000)
        Else
            GetHTTP = ""
        End If
    End Function


    Public Function GetFile(httpURL As String, filename As String) As Boolean
        Dim session As New NotesSession
        Dim retries As Integer
        Dim stream As NotesStream
        Dim flag As Boolean
        Dim responsebody As variant
        Dim cnt As Long
        Dim buffer As String
        Dim tmp As Byte

        Set stream = session.CreateStream
        retries = 0     
        Do
            If retries>1 Then
                Sleep 1     ' After the two first calls, introduce a 1 second delay betwen each additional call
            End If
            retries = retries + 1   
            Call httpObject.open("GET", httpURL, False)
            Call httpObject.send()
            httpStatus = httpObject.Status
            If retries >= 10 Then
                httpStatus = 0  ' Timeout
            End If
        Loop Until httpStatus = 200 Or httpStatus > 500 Or httpStatus = 404  Or httpStatus = 0
        If httpStatus = 200 Then
            flag = stream.Open(filename, "binary")
            If flag = False Then
                MsgBox "Failed to create " & filename & "..."
                GetFile = False 
                Exit function
            End If
            responsebody = httpObject.ResponseBody
            ForAll r in responsebody
                tmp = r
                Call Stream.Write(Chr$(CInt(tmp)))
                cnt = cnt + 1
            End ForAll
            MsgBox cnt
            GetFile = True
        Else
            GetFile = False
        End If

    End Function

    Private Function getString(ByVal StringBin As string)
        Dim intCount As Long
        getString =""
        For intCount = 1 To LenB(StringBin)
            getString = getString & Chr( Asc(MidB(StringBin, intCount, 1)) )
        Next
    End Function

End Class

回答2:

If your code will be running on Windows, you can use either WinHTTP or XMLHTTP COM classes to read web pages. If the code will be running on any other platform, you will be better off using Java instead of LotusScript.

回答3:

If You're trying to read form a NotesField, you could go for below approach. Tha Class was created to specifically handle export of RichText items into html-strings in order to find the otherwise kind-of-hidden embedded images (pasted graphics) that may exist in NotesRichText items. The function ExportDoc() copies the html response text into a user defined field on the document at hand:

Public Class RTExporter
    session As NotesSession
    db As NotesDatabase
    doc As NotesDocument
    obj As Variant
    url As String

    Public Sub New()
        Set Me.session = New NotesSession()
        Set db = session.CurrentDatabase
        Set obj = CreateObject("Microsoft.XMLHTTP")
    End Sub

    ' Handles export from eventual NotesRichTextitems in the form of HTml
    Public Function ExportDoc(hostUrl As String, doc As NotesDocument, rtFieldName As String, htmlFieldName As String)
        Dim htmlString As String    

        url = hostUrl & Me.db.FilePath & "/0/" & doc.Universalid & "/" & rtFieldname & "?openfield&charset=utf-8        

        Set Me.doc = doc    

        htmlString = GetHtmlFromField(htmlFieldName)

        Call doc.ReplaceItemValue(htmlFieldName, htmlString)

        Call doc.Save(True, False)
    End Function

    ' Get http response text and store it in <fieldname>
    Private Function GetHtmlFromField(rtFieldName As String) As String
        Dim html As String      

        On Error Goto ERH

        obj.open "GET", Me.url, False, "", ""

        obj.send("")

        GetHtmlFromField = Trim$(obj.responseText)

        Exit Function
ERH:
        GetHtmlFromField = "Error " & Err & ": " & Error & " occured on line: " & Erl
    End Function

End Class

来源：https://stackoverflow.com/questions/12719192/get-a-field-value-from-a-webpage-lotusscript