Use ArcView geocoding functions to locate addresses

Summary

The View.Locate address finding function is fairly rigid in operation, it only accepts the highest score. The code in this article will allow you to pick an address match based on a list of possible matches.

Procedure

1. Open a new script window.
   
   
   A. Activate the Project window.
   B. Click the Scripts icon.
   C. Click New.
   
   
2. Copy the following code into the script window:
   
   

   Code:
   '-- Script: ModLocat.ave
   
   '-- This script allows you to modify the operation normally handled
   '-- by the View.Locate script. It asks for an input address and
   '-- searches for candidates. If no candidates are found, the 
   '-- user is told and the process is safely stopped. If there is
   '-- one candidate found, the point is located and placed on the
   '-- view. If there are more candidates found, the user is given a
   '-- choice to pick one. The number of the chosen candidate is
   '-- sent back to the MatchCase object, to pull out the correct
   '-- candidate. A point is the located and placed on the view.
   
   '-- Prepare the geocoding scenario
   theView = av.GetActiveDoc
   theGL=theView.GetGraphics
   theTheme = theView.FindTheme("Streets")
   input = msgbox.Multiinput("Enter an address: ", "Input",
        {"House Number: ", "Street Name: "}, {"", ""})
   if (input = nil) then
       exit
   end
   
   hsenumber = input.get(0)
   name = input.get(1)
   addrinput = hsenumber++name
   msgbox.info(addrinput, "Is this the address?")
   
   aMatchSource = theTheme.GetMatchSource
   aMatchSource.OpenIndex
   aMatchKey = Matchkey.Make("us_addr.stn")
   aMatchKey.AllowIntersections("us_intsc.stn", "&")
   aMatchCase = MatchCase.Make(aMatchSource, aMatchKey)
   aMatchCase.AllowIntersections(aMatchSource, aMatchKey)
   
   '-- Match the user-input address to the GBF
     aMatchKey.SetKey(addrinput)
     numcand = aMatchSource.Search(aMatchKey, 80, aMatchCase) 
   
   '-- If there are no candidates
     if (numCand = 0) then
       msgbox.info("Cannot locate address"+NL+"No candidates","")
       exit
     end
   
   '-- If there is only one candidate
     if (numCand = 1) then
        aMatchCase.ScoreCandidates
        cand = aMatchCase.GetBestCand
        thePt=aMatchSource.GetPoint(cand)
        theGPt=GraphicShape.Make(thePt)
        theGL.Add(theGPt)
        theView.Invalidate
        exit
     end
   
   '-- If there is more than 1 candidate
     addrList = {}
     if (numCand > 1) then
       aMatchCase.ScoreCandidates
       msgbox.info(numCand.asstring, "This is the number of candidates")
        for each int in 1..numCand
           cand = aMatchCase.getnthCand(int)
           addrstr = cand.GetValue(aMatchSource.GetMatchFields.Get(4))
           addrstr2 = cand.GetValue(aMatchSource.GetMatchFields.Get(5))
           addrstr4 = cand.GetValue(aMatchSource.GetMatchFields.Get(6))
           addrstr6 = cand.GetValue(aMatchSource.GetMatchFields.Get(7))       
           'addrinfo = addrstr.trim++addrstr2.trim++addrstr4.trim++addrstr6.trim++int.asstring
           addrinfo = addrstr2.trim++int.asstring++cand.getscore.asstring
           addrList.Add(addrinfo)
        end
   
        theChosenAddrRaw = msgbox.ListAsString(addrList, "Choose one of the following:", 
        "Select which address you want to be the match")
        theCandNumber=theChosenAddrRaw.extract(theChosenAddrRaw.Aslist.Count - 2).asnumber
        theFinalCand = aMatchCase.getnthCand(theCandNumber)
        thePt=aMatchSource.GetPoint(theFinalCand)
        theGPt=GraphicShape.Make(thePt)
        theGL.Add(theGPt)
        theView.Invalidate
     end
   

   
   
3. Use the Theme Properties dialog box to rename the geocodable theme (the streets layer) to be Streets.
4. Make the view active document.
5. Click the script window and compile the script by clicking the
   
   button.
6. Click the
   
   button to run the script.