What’s you gut answer right now; without reading the rest of this post?
In my (seemingly) never-ending quest along the path of Uncapacitated Facility Location problems, I found myself thinking if I would be better of write some core functions in C (unmanaged) and calling them in my VB.net project? I thought that it probably would be, but decided to check first. Here’s the link, you can skip to the conclusion at the end for the low-down:
http://www.grimes.demon.co.uk/dotnet/man_unman.htm
Today I have been I’r'een mostly messing about with Map Point.
The following code (called with the GetDistance sub) will return the distance between 2 post codes. To use this code as is, you’ll need to select 2 adjacent cells (i.e. A1 and B1), the distance will be put in the 3rd column along (i.e C1). Clearly you will need Map Point installed also. It’s late bound, but I have not tested the error and checking code should Map Point not be on the machine. I have version 2004 of Map Point and I didn’t have much joy in automating pervious version, but give it a try anyway!
[VBA]Option Explicit
Global gObjApp As Object ”’Golbal deleration for the Map Point Object
Sub GetDistance()
   Dim cell As Excel.Range
   Dim i As Long
If gObjApp Is Nothing Then
OpenMapPointApp
If gObjApp Is Nothing Then ‘ check app was established ok
Exit Sub
Else: End If
Else: End If
   For i = 1 To Selection.Rows.Count
    Selection.Cells(i, 3) = GRD(Selection.Cells(i, 1), Selection.Cells(i, 2))
   Next
If gObjApp Is Nothing Then
Else:
CloseMapPointApp
End If
End Sub
Sub OpenMapPointApp()
On Error GoTo LEH
  Set gObjApp = CreateObject(“MapPoint.Application”)
   gObjApp.Visible = False
   ‘gObjApp.UserControl = True
   Exit Sub
LEH:
MsgBox “Sorry Could not open a Map Point Application, bummer! – Ross” _
, vbOKOnly + vbCritical, “M.I.E Map Point thing”
End Sub
Sub CloseMapPointApp()
”’Change saved property to ture for the the active (and only) map,
”’stops any maessage getting displayed
   gObjApp.ActiveMap.Saved = True
   gObjApp.Quit
   Set gObjApp = Nothing
End Sub
‘—————————————————————————————
‘ Function : GetRouteDistance
‘ DateTime : 18/04/2006 16:04
‘ Author   : rmclean
‘ Purpose  : Gets the routed distacne between 2 way points using an already opened
‘Â Â Â Â Â Â Â Â Â Â Â Â Map Point Object.
‘—————————————————————————————
Function GRD(sPCFrom As String, sPCTo As String)
On Error GoTo LEH
   With gObjApp.ActiveMap.ActiveRoute
       .Clear
       .Waypoints.Add gObjApp.ActiveMap.FindAddressResults(PostalCode:=sPCFrom, Country:=0)(1)
       .Waypoints.Add gObjApp.ActiveMap.FindAddressResults(PostalCode:=sPCTo, Country:=0)(1)
       .Calculate
       GRD = .Distance
   End With
Exit Function
LEH:
”’There could be a few reasons for an erorr, proably could not
”’match the post code, I dont care that much, just need to return
”’ a good anwser.
GRD = “Could Not Route”
End Function[/VBA]
I have used the LocaleID of the user’s computer for the country value (…FindAddressResults(PostalCode:=sPCFrom, Country:=0)…) the full list is here: GeoCountry values
bon!