我对编码还是很陌生，所以如果我问的不是正确的问题，请原谅我。
我有一个JSON文件，其中包含来自多个国家/地区的数据，我想使用Leaflet在地图上绘制该文件中的所有国家/地区。为此，我使用的是包含世界所有国家/地区的GeoJSON文件，并且我想通过“ id”（这是一个3个字母的国家/地区代码）过滤该GeoJSON文件，以使其仅包含数组中的国家/地区（也是3个字母的国家/地区代码）。
我使用D3.json从JSON文件中获取仅包含国家/地区代码的数组，然后遍历该数组以获取列表中的每个国家/地区来过滤我的GeoJSON文件：
d3.json("countryList.json", function(data) {
const countries = [...new Set(data.map(d => d.country))];
console.log(countries);
for (var i = 0; i < countries.length; i++) {
var countryCode = countries[i];
console.log(countryCode);
};
我没有运气尝试过：
L.geoJson(data, {
filter: function(feature) }
if (feature.id === countryCode) return True
}
};
您不需要d3即可过滤您的国家。另外，在for循环内初始化变量时，除非您退出循环，否则它将被覆盖。无论如何，以从2个州中过滤单个美国州的示例为例，然后从那里开始：
var geojson_data = {"type":"FeatureCollection","features":[{"type":"Feature","id":"36","properties":{"name":"New York"},"geometry":{"type":"Polygon","coordinates":[[[-73.343806,45.013027],[-73.332852,44.804903],[-73.387622,44.618687],[-73.294514,44.437948],[-73.321898,44.246255],[-73.436914,44.043608],[-73.349283,43.769761],[-73.404052,43.687607],[-73.245221,43.523299],[-73.278083,42.833204],[-73.267129,42.745573],[-73.508114,42.08834],[-73.486206,42.050002],[-73.55193,41.294184],[-73.48073,41.21203],[-73.727192,41.102491],[-73.655992,40.987475],[-73.22879,40.905321],[-73.141159,40.965568],[-72.774204,40.965568],[-72.587988,40.998429],[-72.28128,41.157261],[-72.259372,41.042245],[-72.100541,40.992952],[-72.467496,40.845075],[-73.239744,40.625997],[-73.562884,40.582182],[-73.776484,40.593136],[-73.935316,40.543843],[-74.022947,40.708151],[-73.902454,40.998429],[-74.236547,41.14083],[-74.69661,41.359907],[-74.740426,41.431108],[-74.89378,41.436584],[-75.074519,41.60637],[-75.052611,41.754247],[-75.173104,41.869263],[-75.249781,41.863786],[-75.35932,42.000709],[-79.76278,42.000709],[-79.76278,42.252649],[-79.76278,42.269079],[-79.149363,42.55388],[-79.050778,42.690804],[-78.853608,42.783912],[-78.930285,42.953697],[-79.012439,42.986559],[-79.072686,43.260406],[-78.486653,43.375421],[-77.966344,43.369944],[-77.75822,43.34256],[-77.533665,43.233021],[-77.391265,43.276836],[-76.958587,43.271359],[-76.695693,43.34256],[-76.41637,43.523299],[-76.235631,43.528776],[-76.230154,43.802623],[-76.137046,43.961454],[-76.3616,44.070993],[-76.312308,44.196962],[-75.912491,44.366748],[-75.764614,44.514625],[-75.282643,44.848718],[-74.828057,45.018503],[-74.148916,44.991119],[-73.343806,45.013027]]]}},{"type":"Feature","id":"48","properties":{"name":"Texas"},"geometry":{"type":"Polygon","coordinates":[[[-101.812942,36.501861],[-100.000075,36.501861],[-100.000075,34.563024],[-99.923398,34.573978],[-99.698843,34.382285],[-99.57835,34.415147],[-99.260688,34.404193],[-99.189488,34.2125],[-98.986841,34.223454],[-98.767763,34.135823],[-98.570593,34.146777],[-98.488439,34.064623],[-98.36247,34.157731],[-98.170777,34.113915],[-98.088623,34.004376],[-97.946222,33.987946],[-97.869545,33.851022],[-97.694283,33.982469],[-97.458774,33.905791],[-97.371143,33.823637],[-97.256128,33.861976],[-97.173974,33.736006],[-96.922034,33.960561],[-96.850834,33.845545],[-96.631756,33.845545],[-96.423633,33.774345],[-96.346956,33.686714],[-96.149786,33.840068],[-95.936185,33.889361],[-95.8376,33.834591],[-95.602092,33.933176],[-95.547322,33.878407],[-95.289906,33.87293],[-95.224183,33.960561],[-94.966767,33.861976],[-94.868182,33.74696],[-94.484796,33.637421],[-94.380734,33.544313],[-94.183564,33.593606],[-94.041164,33.54979],[-94.041164,33.018527],[-94.041164,31.994339],[-93.822086,31.775262],[-93.816609,31.556184],[-93.542762,31.15089],[-93.526331,30.93729],[-93.630393,30.679874],[-93.728978,30.575812],[-93.696116,30.438888],[-93.767317,30.334826],[-93.690639,30.143133],[-93.926148,29.787132],[-93.838517,29.688547],[-94.002825,29.68307],[-94.523134,29.546147],[-94.70935,29.622824],[-94.742212,29.787132],[-94.873659,29.672117],[-94.966767,29.699501],[-95.016059,29.557101],[-94.911997,29.496854],[-94.895566,29.310638],[-95.081782,29.113469],[-95.383014,28.867006],[-95.985477,28.604113],[-96.045724,28.647929],[-96.226463,28.582205],[-96.23194,28.642452],[-96.478402,28.598636],[-96.593418,28.724606],[-96.664618,28.697221],[-96.401725,28.439805],[-96.593418,28.357651],[-96.774157,28.406943],[-96.801542,28.226204],[-97.026096,28.039988],[-97.256128,27.694941],[-97.404005,27.333463],[-97.513544,27.360848],[-97.540929,27.229401],[-97.425913,27.262263],[-97.480682,26.99937],[-97.557359,26.988416],[-97.562836,26.840538],[-97.469728,26.758384],[-97.442344,26.457153],[-97.332805,26.353091],[-97.30542,26.161398],[-97.217789,25.991613],[-97.524498,25.887551],[-97.650467,26.018997],[-97.885976,26.06829],[-98.198161,26.057336],[-98.466531,26.221644],[-98.669178,26.238075],[-98.822533,26.369522],[-99.030656,26.413337],[-99.173057,26.539307],[-99.266165,26.840538],[-99.446904,27.021277],[-99.424996,27.174632],[-99.50715,27.33894],[-99.479765,27.48134],[-99.605735,27.640172],[-99.709797,27.656603],[-99.879582,27.799003],[-99.934351,27.979742],[-100.082229,28.14405],[-100.29583,28.280974],[-100.399891,28.582205],[-100.498476,28.66436],[-100.629923,28.905345],[-100.673738,29.102515],[-100.799708,29.244915],[-101.013309,29.370885],[-101.062601,29.458516],[-101.259771,29.535193],[-101.413125,29.754271],[-101.851281,29.803563],[-102.114174,29.792609],[-102.338728,29.869286],[-102.388021,29.765225],[-102.629006,29.732363],[-102.809745,29.524239],[-102.919284,29.190146],[-102.97953,29.184669],[-103.116454,28.987499],[-103.280762,28.982022],[-103.527224,29.135376],[-104.146119,29.381839],[-104.266611,29.513285],[-104.507597,29.639255],[-104.677382,29.924056],[-104.688336,30.181472],[-104.858121,30.389596],[-104.896459,30.570335],[-105.005998,30.685351],[-105.394861,30.855136],[-105.602985,31.085167],[-105.77277,31.167321],[-105.953509,31.364491],[-106.205448,31.468553],[-106.38071,31.731446],[-106.528588,31.786216],[-106.643603,31.901231],[-106.616219,31.999816],[-103.067161,31.999816],[-103.067161,33.002096],[-103.045254,34.01533],[-103.039777,36.501861],[-103.001438,36.501861],[-101.812942,36.501861]]]}}]}
L.geoJSON(geojson_data, {
filter: function(feature) {
return feature.properties.name === "Texas";
}
}).addTo(map);
谢谢！但是我需要以某种方式从我的JSON文件中为一系列国家/地区替换“ Texas”，以便它只为这些国家/地区过滤GeoJSON。这可能吗，还是最好编辑我的GeoJSON文件？