This example uses OpenLayers v10.9.0. The latest is v.
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#### Constrained Extent

view 2 extent 5 constrain 1 restrict 1

#####

Example of a view with a constrained extent.

This map has a view that is constrained in an extent. This is done using the `extent` view option. Please note that specifying `constrainOnlyCenter: true` would only apply the extent restriction to the view center.

##### main.js

    import Map from 'ol/Map.js';
    import View from 'ol/View.js';
    import ZoomSlider from 'ol/control/ZoomSlider.js';
    import {defaults as defaultControls} from 'ol/control/defaults.js';
    import TileLayer from 'ol/layer/Tile.js';
    import OSM from 'ol/source/OSM.js';

    const view = new View({
      center: [328627.563458, 5921296.662223],
      zoom: 8,
      extent: [-572513.341856, 5211017.966314, 916327.095083, 6636950.728974],
    });

    new Map({
      layers: [
        new TileLayer({
          source: new OSM(),
        }),
      ],
      keyboardEventTarget: document,
      target: 'map',
      view: view,
      controls: defaultControls().extend([new ZoomSlider()]),
    });

##### index.html

    <!DOCTYPE html>
    <html lang="en">
      <head>
        <meta charset="UTF-8">
        <title>Constrained Extent</title>
        <link rel="stylesheet" href="node_modules/ol/ol.css">
        <style>
          .map {
            width: 100%;
            height: 400px;
          }
        </style>
      </head>
      <body>
        <div id="map" class="map"></div>

        <script type="module" src="main.js"></script>
      </body>
    </html>

##### package.json

    {
      "name": "extent-constrained",
      "dependencies": {
        "ol": "10.9.0"
      },
      "devDependencies": {
        "vite": "^3.2.3"
      },
      "scripts": {
        "start": "vite",
        "build": "vite build"
      }
    }