develop/jsapi3/search_with_html5_location/step_1.html

<!DOCTYPE HTML>
<html>
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="initial-scale=1, maximum-scale=1,user-scalable=no">
  <title>Locate Button</title>
  <link rel="stylesheet" href="https://js.arcgis.com/3.16/esri/css/esri.css">
  <style>
    html, body, #map {
      padding:0;
      margin:0;
      height:100%;
    }
    #LocateButton {
      position: absolute;
      top: 95px;
      left: 20px;
      z-index: 50;
    }
  </style>
  <script src="https://js.arcgis.com/3.16/"></script>
  <script>
    var map;

    require([
      "esri/map",
      "esri/dijit/LocateButton",
      "dojo/domReady!"
    ], function(
      Map, LocateButton
    )  {

      map = new Map("map", {
        center: [-56.049, 38.485],
        zoom: 3,
        basemap: "streets"
      });

      geoLocate = new LocateButton({
        map: map
      }, "LocateButton");
      geoLocate.startup();

      /* these are the samples i ripped off
      https://developers.arcgis.com/javascript/jssamples/widget_locate.html
      https://developers.arcgis.com/javascript/jssamples/fl_selection.html
      https://developers.arcgis.com/javascript/jssamples/query_nomap.html
      */
    });
  </script>
</head>
<body>
  <div id="map" class="map">
    <div id="LocateButton"></div>
  </div>
</body>
</html>