具有半径的地图限制

Question

如何将地图限制在一个类别中 就像打开地图一样，它将自动选择半径50米范围内的所有附近公园。

我需要在项目中放入什么插件和代码。

`
var mymap = L.map('mapid').fitWorld(); L.tileLayer('https://api.tiles.mapbox.com/v4/{id}/{z}/{x}/{y}.png?access_token=access token', {
    attribution: 'Map data &copy; <a href="https://www.openstreetmap.org/">OpenStreetMap</a> contributors, <a href="https://creativecommons.org/licenses/by-sa/2.0/">CC-BY-SA</a>, Imagery © <a href="https://www.mapbox.com/">Mapbox</a>',
    maxZoom: 20,
    id: 'mapbox.streets',
    accessToken: 'access token'
}).addTo(mymap);

	mymap.locate({setView: true, maxZoom: 20});

function onLocationFound(e) {
    var radius = e.accuracy / 2;

    L.marker(e.latlng).addTo(mymap)
        .bindPopup("You are within " + radius + " meters from this point").openPopup();

    L.circle(e.latlng, radius).addTo(mymap);
}

mymap.on('locationfound', onLocationFound);
var popup = L.popup();

function onMapClick(e) {
    popup
        .setLatLng(e.latlng)
        .setContent("You clicked the map at " + e.latlng.toString())
        .openOn(mymap);
}

mymap.on('click', onMapClick);`