ArcGIS JavaScript API - Basemap toggle

arcgis-basemap-toggle.js

/* Adds a map control to select a basemap. Requires a div with id="basemap-toggle" inside the map div.
 *
 * function name: BasemapToggle
 * module name: "esri/dijit/BasemapToggle"
 * documentation: https://developers.arcgis.com/javascript/jssamples/widget_toggle.html
 * example: http://developers.arcgis.com/javascript/samples/widget_toggle/
 */
 
let toggle = new BasemapToggle({
  map: map,
  basemap: "hybrid"
}, "basemap-toggle").startup();