Here’s some VB code I pulled out of dbWalker that shows how to grab a COS entry and check a transfer string against it’s transfer restriction table rules. Unfortunately when I paste it in here it loses all it's indentation and color so it's not as fabulously readable as it is in my dev environment. Also, just in case one of my former Computer Science professors is reading this, I've yanked out the error handling code here to make it shorter - honest.
Just for review here – restriction tables are a collection of pattern matching strings made up of numbers and wildcard characters and an “allow” or “don’t allow” flag – they are processed in order from top to bottom until the dial string matches and the allow/don’t is evaluated. The last rule is always “*” which will match anything so you’re guaranteed a rule will match.
For this routine, you pass in the Class of Service ObjectID of the subscriber and the transfer string you want to check and it returns True or False depending on if the string is allowed by that COS transfer restriction table or not.
This code uses a nifty little VBScript object called RegExp which is a RegularExpression object. To use it in VB you need to include the “Microsoft VBScript Regular Expressions 5.5” object in your project references.
Private Function IsTransferStringLegal(strStringToCheck as String, strCOSObjectID as string) as Boolean
Dim rsRT As ADODB.Recordset
Dim rsPatterns As ADODB.Recordset
Dim rsCOS as ADODB.Recordset
Dim strPattern As String
Dim myRegExp As New RegExp
If Len(strStringToCheck) = 0 Then
'We assume that an empty string is legal
IsTransferStringLegal=True
Exit
End If
‘Assume false here
IsTransferStringLegal=false
‘Setup the regular expression object here
myRegExp.IgnoreCase = True
myRegExp.Global = False
Set rsCOS=New ADODB.Recordset
rsCOS.Open "SELECT * FROM vw_COS WHERE COSObjectID='" + strCOSObjectID + "'",strConnectionString, adOpenKeySet, adLockReadOnly
If rsCOS.RecordCount=0 Then
Msgbox ”(error) could not find COS reference”
Exit
End If
Set rsRT = New ADODB.Recordset
rsRT.Open "SELECT * FROM vw_RestrictionTable WHERE RestrictionObjectID="+ rsCOS("XferRestrictionObjectID") + "'", strConnectionString, adOpenKeyset, adLockReadOnly
If rsRT.Recordcount=0 Then
MsgBox”(error) could not find restriction table for transfer”
Exit
End If
‘Pull the patterns associated with the restriction table out. Be sure to preserve the “index” order since the order in which they’re evaluated is important.
Set rsPatterns = New ADODB.Recordset
rsPatterns.CursorLocation = adUseClient
rsPatterns.Open "Select * from VW_RestrictionPattern WHERE ParentObjectID='" + rsRT("RestrictionObjectID") + "' ORDER BY [Index]", strConnectionString, adOpenStatic, adLockReadOnly
If rsPatterns.RecordCount = 0 Then
MsgBox ”(error) no restriction table patterns found for restriction table”
Exit
End If
'do that regular expression thing, baby!
'First, strip out all commas
strStringToCheck = Replace(strStringToCheck, ",", "", , , vbTextCompare)
‘Now run through each pattern and see if it matches the dial string we’re looking at.
rsPatterns.MoveFirst
Do While rsPatterns.EOF = False
strPattern = rsPatterns("NumberPattern")
'replace ?s with .s to match the regular expression format.
strPattern = Replace(strPattern, "?", ".", , , vbTextCompare)
'replace * with "[0-9]*" to match the regular expression format.
strPattern = Replace(strPattern, "*", "[0-9]*", , , vbTextCompare)
myRegExp.Pattern = strPattern
If myRegExp.Test(strStringToCheck) = True Then
‘OK, the transfer string matches this pattern
If rsPatterns("Blocked") = True Then
‘the transfer string is not allowed – just exit since the function value is false
Else
‘the transfer string is allowed
IsTransferStringLegal=true
End If
Exit Do
End If
rsPatterns.MoveNext
Loop
'clean up and pull the rip cord.
On Error Resume Next
rsRT.Close
Set rsRT = Nothing
rsPatterns.Close
Set rsPatterns = Nothing
rsCOS.Close
Set rsCOS=Nothing
End Sub
