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Encoding methods

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JavaScript
var poly;

function initialize() {
  var mapOptions = {
    zoom: 14,
    center: new google.maps.LatLng(34.3664951, -89.5192484)
  };

  var map = new google.maps.Map(document.getElementById('map-canvas'),
    mapOptions);

  var polyOptions = {
    strokeColor: '#000000',
    strokeOpacity: 1.0,
    strokeWeight: 3,
    map: map
  };
  poly = new google.maps.Polyline(polyOptions);

  // Add a listener for the click event
  google.maps.event.addListener(map, 'click', addLatLng);
}

/**
 * Handles click events on a map, and adds a new point to the Polyline.
 * Updates the encoding text area with the path's encoded values.
 */
function addLatLng(event) {
  var path = poly.getPath();
  // Because path is an MVCArray, we can simply append a new coordinate
  // and it will automatically appear
  path.push(event.latLng);

  // Update the text field to display the polyline encodings
  var encodeString = google.maps.geometry.encoding.encodePath(path);
  if (encodeString) {
    document.getElementById('encoded-polyline').value = encodeString;
  }
}

google.maps.event.addDomListener(window, 'load', initialize);
JavaScript + HTML
<!DOCTYPE html>
<html>
  <head>
    <title>Encoding methods</title>
    <meta name="viewport" content="initial-scale=1.0, user-scalable=no">
    <meta charset="utf-8">
    <style>
      html, body, #map-canvas {
        height: 100%;
        margin: 0;
        padding: 0;
      }

      #panel {
        position: absolute;
        top: 5px;
        left: 50%;
        margin-left: -180px;
        z-index: 5;
        background-color: #fff;
        padding: 5px;
        border: 1px solid #999;
      }

      /*
      Provide the following styles for both ID and class,
      where ID represents an actual existing "panel" with
      JS bound to its name, and the class is just non-map
      content that may already have a different ID with
      JS bound to its name.
      */

      #panel, .panel {
        font-family: 'Roboto','sans-serif';
        line-height: 30px;
        padding-left: 10px;
      }

      #panel select, #panel input, .panel select, .panel input {
        font-size: 15px;
      }

      #panel select, .panel select {
        width: 100%;
      }

      #panel i, .panel i {
        font-size: 12px;
      }

    </style>
    <script src="https://maps.googleapis.com/maps/api/js?v=3.exp&signed_in=true&libraries=geometry"></script>
    <script>
var poly;

function initialize() {
  var mapOptions = {
    zoom: 14,
    center: new google.maps.LatLng(34.3664951, -89.5192484)
  };

  var map = new google.maps.Map(document.getElementById('map-canvas'),
    mapOptions);

  var polyOptions = {
    strokeColor: '#000000',
    strokeOpacity: 1.0,
    strokeWeight: 3,
    map: map
  };
  poly = new google.maps.Polyline(polyOptions);

  // Add a listener for the click event
  google.maps.event.addListener(map, 'click', addLatLng);
}

/**
 * Handles click events on a map, and adds a new point to the Polyline.
 * Updates the encoding text area with the path's encoded values.
 */
function addLatLng(event) {
  var path = poly.getPath();
  // Because path is an MVCArray, we can simply append a new coordinate
  // and it will automatically appear
  path.push(event.latLng);

  // Update the text field to display the polyline encodings
  var encodeString = google.maps.geometry.encoding.encodePath(path);
  if (encodeString) {
    document.getElementById('encoded-polyline').value = encodeString;
  }
}

google.maps.event.addDomListener(window, 'load', initialize);

    </script>
  </head>
  <body>
    <div id="map-canvas" style="width: 50%; float:left"></div>
    <div style="width:46%; float:left" class="panel">
      <div>Encoding:</div>
      <textarea id="encoded-polyline" style="height: 100px; width: 100%"></textarea>
    </div>
  </body>
</html>

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