Change the case of labels | Mapbox GL JS

Use the upcase and downcase expressions to change the case of labels.

JavaScript

React

JavaScript

React


<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Change the case of labels</title>
<meta name="viewport" content="initial-scale=1,maximum-scale=1,user-scalable=no">
<link href="https://api.mapbox.com/mapbox-gl-js/v3.8.0/mapbox-gl.css" rel="stylesheet">
<script src="https://api.mapbox.com/mapbox-gl-js/v3.8.0/mapbox-gl.js"></script>
<style>
body { margin: 0; padding: 0; }
#map { position: absolute; top: 0; bottom: 0; width: 100%; }
</style>
</head>
<body>
<div id="map"></div>
<script>
	// TO MAKE THE MAP APPEAR YOU MUST
	// ADD YOUR ACCESS TOKEN FROM
	// https://account.mapbox.com
	mapboxgl.accessToken = 'YOUR_MAPBOX_ACCESS_TOKEN';
    const map = new mapboxgl.Map({
        container: 'map', // container ID
        // Choose from Mapbox's core styles, or make your own style with Mapbox Studio
        style: 'mapbox://styles/mapbox/outdoors-v12', // style URL
        center: [-116.231, 43.604], // starting position [lng, lat]
        zoom: 11 // starting zoom
    });

    map.on('load', () => {
        // data from opendata.cityofboise.org/
        map.addSource('off-leash-areas', {
            'type': 'geojson',
            'data': 'https://docs.mapbox.com/mapbox-gl-js/assets/boise.geojson'
        });
        map.addLayer({
            'id': 'off-leash-areas',
            'type': 'symbol',
            'source': 'off-leash-areas',
            'layout': {
                'text-field': [
                    'format',
                    ['upcase', ['get', 'FacilityName']],
                    { 'font-scale': 0.8 },
                    '\n',
                    {},
                    ['downcase', ['get', 'Comments']],
                    { 'font-scale': 0.6 }
                ],
                'text-font': ['Open Sans Semibold', 'Arial Unicode MS Bold']
            }
        });
    });
</script>

</body>
</html>

This code snippet will not work as expected until you replace YOUR_MAPBOX_ACCESS_TOKEN with an access token from your Mapbox account.

JavaScript

React


import React, { useEffect, useRef } from 'react';
import mapboxgl from 'mapbox-gl';
import 'mapbox-gl/dist/mapbox-gl.css';

const MapboxExample = () => {
  const mapContainerRef = useRef();
  const mapRef = useRef();

  useEffect(() => {
    // TO MAKE THE MAP APPEAR YOU MUST
    // ADD YOUR ACCESS TOKEN FROM
    // https://account.mapbox.com
    mapboxgl.accessToken = 'YOUR_MAPBOX_ACCESS_TOKEN';

    mapRef.current = new mapboxgl.Map({
      container: mapContainerRef.current,
      style: 'mapbox://styles/mapbox/outdoors-v12',
      center: [-116.231, 43.604],
      zoom: 11
    });

    mapRef.current.on('load', () => {
      mapRef.current.addSource('off-leash-areas', {
        type: 'geojson',
        data: 'https://docs.mapbox.com/mapbox-gl-js/assets/boise.geojson'
      });
      mapRef.current.addLayer({
        id: 'off-leash-areas',
        type: 'symbol',
        source: 'off-leash-areas',
        layout: {
          'text-field': [
            'format',
            ['upcase', ['get', 'FacilityName']],
            { 'font-scale': 0.8 },
            '\n',
            {},
            ['downcase', ['get', 'Comments']],
            { 'font-scale': 0.6 }
          ],
          'text-font': ['Open Sans Semibold', 'Arial Unicode MS Bold']
        }
      });
    });
  }, []);

  return <div ref={mapContainerRef} id="map" style={{ height: '100%' }}></div>;
};

export default MapboxExample;

This code snippet will not work as expected until you replace YOUR_MAPBOX_ACCESS_TOKEN with an access token from your Mapbox account.

Additional Developer Resources

Mapbox Developer Discord

Developer Cheatsheet

Mapbox Support

Ask AI

Was this example helpful?