Google Maps API - Batch Geocoder

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Getting lat/lngs in batch".

About

NOTE: This page is a daughter page of: Google Maps API


This piece of code allows you to paste in a (new line sepearated) list of address, and will try to resolve all of them to a lat/lng, which it shows on the map, and output to a textarea for you to copy/paste into a spreadsheet program if desired. Going from a text address (eg: "1 Main Street, Sydney, NSW") to lat/lng coordinates is called "geocoding".


NOTE: If you only need 1 lat/lng... or want to "reverse geocode" (from lat/lng to text address) try www.latlong.net.


Showing a Thumbnail And Map of a Place

<!DOCTYPE html>
<html>
  <head>
    <meta charset="utf-8">
    <title>Batch Geocoder</title>
    <style>
      html, body, #map-canvas {
        height: 100%;
        margin: 0px;
        padding: 0px
      }
      textarea {
        vertical-align: top;
        font-size: 90%;
      }
      #btn-geocode {
        vertical-align: top;
      }
      #panel {
        position: absolute;
        top: 5px;
        left: 50%;
        margin-left: -400px;
        z-index: 5;
        background-color: #fff;
        padding: 5px;
        border: 1px solid #999;
      }
    </style>
    <script src="https://maps.googleapis.com/maps/api/js?v=3.exp&signed_in=true"></script>
    <script>
var geocoder;
var map;
function initialize() {
  geocoder = new google.maps.Geocoder();
  var latlng = new google.maps.LatLng(-34.397, 150.644);
  var mapOptions = {
    zoom: 8,
    center: latlng
  }
  map = new google.maps.Map(document.getElementById('map-canvas'), mapOptions);
}
 
/**
 * Appends the given line to 'txt-coordinates' textarea, followed by a newline.
 * @param {string} outputLine Line of text to output.
 */
function addLineToOutput(outputLine) {
  var text = document.getElementById('txt-coordinates').value;
  document.getElementById('txt-coordinates').value = text + outputLine + '\n'
}
 
/**
 * Tries to geocode an address and, if successful, adds a marker to the
 * map and writes a lat/lng to 'txt-coordinates' textarea. If lookup fails 
 * (address not found), no marker is added, and prints 'NOMATCH' to the
 * textarea.
 * @param {string} address The address to look up (eg: "Sydney, NSW").
 */
function addPoint(address) {
  geocoder.geocode( { 'address': address }, function(results, status) {
    if (status == google.maps.GeocoderStatus.OK) {
      map.setCenter(results[0].geometry.location);
      var marker = new google.maps.Marker({
          map: map,
          position: results[0].geometry.location,
          title: address
      });
      addLineToOutput(address + '\t' + marker.position.lat() + '\t' + marker.position.lng());
    } else {
      addLineToOutput(address + '\tNOMATCH');
      console.log('Geocoder failed on "' + address + '" due to: ' + status);
    }
  });
}
 
/**
 * Reads 'txt-addresses' textarea, and for each line, looks up that address,
 * writes coordinates out, and adds a marker to the map.
 */
function geocodeAddresses() {
  var allAddresses = document.getElementById('txt-addresses').value;
  document.getElementById('txt-coordinates').value = '';  // Clear output.
  var address = allAddresses.split('\n');
 
  for (var i = 0; i < address.length; i++) {
    // NOTE: An intracacy here is that if you call them all together then
    // the output won't occur in order!
    setTimeout(addPoint, i*100, address[i]);
  }
}
 
google.maps.event.addDomListener(window, 'load', initialize);
 
    </script>
  </head>
  <body>
    <div id="panel">
      <textarea id="txt-addresses" rows="10" cols="40" wrap="off">Sydney
Melbourne
Texas
(1 per line)</textarea>
      <input id="btn-geocode" type="button" value="Geocode >" onclick="geocodeAddresses()">
      <textarea id="txt-coordinates" rows="10" cols="40" wrap="off" readonly>Output appears here</textarea>
    </div>
    <div id="map-canvas"></div>
  </body>
</html>
 
<!-- ACKNOWLEDGEMENTS:
Based on code from: https://developers.google.com/maps/documentation/javascript/examples/geocoding-simple !-->


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