This example uses OpenLayers v10.9.0. The latest is v.
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#### WMS GetFeatureInfo (Layers)

#####

All features: |
Hotel features: |
Restaurant features: |

Shows how to fetch features per layer name in a single WMS GetFeatureInfo request

Demonstrates the use of the `layers` option in the `ol/format/WMSGetFeatureInfo` format object, which allows features returned by a single WMS GetFeatureInfo request that asks for more than one layer to be read by layer name.

##### main.js

    import WMSGetFeatureInfo from 'ol/format/WMSGetFeatureInfo.js';

    fetch('data/wmsgetfeatureinfo/osm-restaurant-hotel.xml')
      .then(function (response) {
        return response.text();
      })
      .then(function (response) {
        // this is the standard way to read the features
        const allFeatures = new WMSGetFeatureInfo().readFeatures(response);
        document.getElementById('all').innerText = allFeatures.length.toString();

        // when specifying the 'layers' options, only the features of those
        // layers are returned by the format
        const hotelFeatures = new WMSGetFeatureInfo({
          layers: ['hotel'],
        }).readFeatures(response);
        document.getElementById('hotel').innerText =
          hotelFeatures.length.toString();

        const restaurantFeatures = new WMSGetFeatureInfo({
          layers: ['restaurant'],
        }).readFeatures(response);
        document.getElementById('restaurant').innerText =
          restaurantFeatures.length.toString();
      });

##### index.html

    <!DOCTYPE html>
    <html lang="en">
      <head>
        <meta charset="UTF-8">
        <title>WMS GetFeatureInfo (Layers)</title>
        <link rel="stylesheet" href="node_modules/ol/ol.css">
        <style>
          .map {
            width: 100%;
            height: 400px;
          }
        </style>
      </head>
      <body>
        <table id="info">
          <tr>
            <td>All features:</td>
            <td id="all"></td>
          </tr>
          <tr>
            <td>Hotel features:</td>
            <td id="hotel"></td>
          </tr>
          <tr>
            <td>Restaurant features:</td>
            <td id="restaurant"></td>
          </tr>
        </table>

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

##### package.json

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