Recursive Function Not Returning - vb.net

Question

I am hopeing someone can help me here with a recursive function I have that is not returning either true or false as I would have espected it to. The function loops through a Active Directory group for its members and then calls itself if it encounters any groups within the membership in order to gets its members as well. I am trying to return either true or false based on if any errors were encountered but not haveing any luck at all. It appears to just hang and never return back to the primary calling sub that starts the recursive function. Below is my code I am using:
Private Sub StartAnalysis(ByVal grp As String, ByVal grpdn As String, ByVal reqid As String)
Dim searchedGroups As New Hashtable
'prior work before calling sub
searchedGroups.Add(grp, 1)
Dim iserror As Boolean = GetGroupMembers(grpdn, searchedGroups, reqid)
If iserror = False Then
'do stuff
Else
'do stuff
End If
'cleanup
End Sub
Public Function GetGroupMembers(ByVal groupSearch As String, ByVal searchedGroups As Hashtable, ByVal requestID As String) As Boolean
Dim iserror As Boolean = False
Try
Dim lastQuery As Boolean = False
Dim endLoop As Boolean = False
Dim rangeStep As Integer = 999
Dim rangeLow As Integer = 0
Dim rangeHigh As Integer = rangeLow + rangeStep
Do
Dim range As String = "member"
If lastQuery = False Then
range = String.Format("member;range={0}-{1}", rangeLow, rangeHigh)
Else
range = String.Format("member;range={0}-*", rangeLow)
endLoop = True
End If
Dim group As SearchResult = QueryObject(groupSearch, range)
Dim groupCN As String = group.Properties("cn")(0).ToString
If group.Properties.Contains(range) Then
For Each member As Object In group.Properties(range)
Dim user As SearchResult = QueryObject(member.ToString, "member")
Dim userCN = user.Properties("cn")(0).ToString
If Not user.Properties.Contains("member") Then
Dim userMail = String.Empty
If user.Properties.Contains("mail") Then
userMail = user.Properties("mail")(0).ToString
End If
userCN = userCN.Replace("'", "''")
Dim qry As String = _
"INSERT INTO group_analysis_details (request_id, member_name, member_email, member_group) " & _
"values ('" & requestID & "', '" & userCN & "', '" & userMail & "', '" & groupCN & "')"
Dim sqlConn As SqlConnection = New SqlConnection(cs)
Dim sqlCmd As SqlCommand = New SqlCommand(qry, sqlConn)
sqlConn.Open()
sqlCmd.ExecuteNonQuery()
sqlConn.Close()
sqlCmd.Dispose()
sqlConn.Dispose()
Else
If Not searchedGroups.ContainsKey(userCN) Then
searchedGroups.Add(userCN, 1)
iserror = GetGroupMembers(user.Properties("distinguishedname")(0).ToString, searchedGroups, requestID)
If iserror = True Then Return iserror
Else
searchedGroups(userCN) += 1
End If
End If
Next
Else
lastQuery = True
End If
If lastQuery = False Then
rangeLow = rangeHigh + 1
rangeHigh = rangeLow + rangeStep
End If
Loop While endLoop = False
Return iserror
Catch ex As Exception
myEvents.WriteEntry("Error while analyzing the following group: " & groupSearch & vbCrLf & vbCrLf & _
"Details of the error are as follows: " & ex.Message, EventLogEntryType.Error)
Return True
End Try
End Function
Hopefully someone can point out where I might be making my error is this.
Thanks,
Ron

Answer 1

Generally if you're using a 'Do...Loop While' and manually setting the exit condition inside the loop it's very easy to get stuck in an infinite loop which is what causes the program to hang.
It looks like you're not setting endloop = True in all circumstances. Try changing it to an Exit Do and adding one to each of the various conditions you have. A bit of trial and error will be required to get it just right.
Also to make your life easier extract the database insert code into a seperate function and call it when needed.