需要使用Turf的“联合”功能来组合来自GeoJSON文件的多组多边形的帮助

Question

有没有人有使用leaflet.js，turf.js和mapbox进行JavaScript映射的经验？我正在尝试使用草皮的并集函数合并从geoJSON文件提取的多个多边形系列。任何帮助将不胜感激！

turf.js联合命令：https://turfjs.org/docs/#union

我正在从GeoJSON文件中调用德克萨斯州的县数据，如下所示。我已经有代码以相同的颜色标记大城市中的县集-参见下文。我正在尝试使用turf.js的并集函数来转换每个集合（例如如下所示的Abilene的3个县和Amarillo的5个县）以为每组县创建统一的（多）多边形，包括消除内部边界和允许每个都被选择为一个单元来显示弹出窗口。

// Creating map object
var map = L.map("map", {
  center: [31, -97],
  zoom: 6
});

// Adding tile layer
L.tileLayer("https://api.tiles.mapbox.com/v4/{id}/{z}/{x}/{y}.png?access_token={accessToken}", {
  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: 18,
  id: "mapbox.streets",
  accessToken: API_KEY
}).addTo(map);

var link = "https://raw.githubusercontent.com/TNRIS/tx.geojson/master/counties/tx_counties.geojson";


// Function that will determine the color of a metropolitan area based on the county it belongs to
function chooseColor(COUNTY) {
  switch (COUNTY) {

//Abilene
case "Callahan County":
  return "pink";
case "Jones County":
  return "pink";
case "Taylor County":
  return "pink";

//Amarillo
case "Armstrong County":
  return "lightgreen";
case "Carson County":
  return "lightgreen";
case "Oldham County":
  return "lightgreen";
case "Potter County":
  return "lightgreen";
case "Randall County":
  return "lightgreen";

  default:
    return "black";
  }
}

// Grabbing our GeoJSON data..
d3.json(link, function(data) {
  // Creating a geoJSON layer with the retrieved data
  L.geoJson(data, {
    style: function(feature) {
      return {
        color: "white",
        fillColor: chooseColor(feature.properties.COUNTY),
        fillOpacity: 1,
        weight: 1.5
      };
    }
  }).addTo(map);
});

无法弄清楚turf.union命令的结构，希望获得帮助！