JSFiddle - React, Tailwind, and code Playground
HTML
<script src="http://openlayers.org/api/OpenLayers.js"></script>
<div id="map" style="width:450px;height:430px;"></div>
JavaScript
var options = {
projection: new OpenLayers.Projection("EPSG:900913"),
'displayProjection': new OpenLayers.Projection("EPSG:4326"),
units: "m",
maxResolution: 156543.0339,
maxExtent: new OpenLayers.Bounds(-20037508.34, -20037508.34,
20037508.34, 20037508.34)
};
map = new OpenLayers.Map('map', options);
// create Google Mercator layers
var osm = new OpenLayers.Layer.OSM();
// create WMS layer
var wms = new OpenLayers.Layer.WMS(
"World Map",
"http://vmap0.tiles.osgeo.org/wms/vmap0",
{'layers': 'basic'},
{ maxExtent:new OpenLayers.Bounds(-30037508.34, -30037508.34, 30037508.34, 30037508.34),
maxResolution: 156543.0339 }
);
map.addLayer(wms);
map.addLayer(osm);
layerControl = new OpenLayers.Control.LayerSwitcher();
map.addControl(layerControl);
var long = 170;
var lat = -45;
var lonlat = new OpenLayers.LonLat(long, lat).transform(map.displayProjection, map.projection);
map.setCenter(lonlat, 4);