编辑地理服务器发布的OpenLayers2中的要素，并将更新后的要素保存在postgres连接的数据库表中

var map = new OpenLayers.Map("map");
var layer = new OpenLayers.Layer.TencentMap("Tencent Map");
map.addLayer(layer);

var featureLayer = new OpenLayers.Layer.Vector("Feature Layer");
map.addLayer(featureLayer);

var modifyControl = new OpenLayers.Control.ModifyFeature(featureLayer);
map.addControl(modifyControl);
modifyControl.activate();

// 选择要素
var selectControl = new OpenLayers.Control.SelectFeature(featureLayer);
map.addControl(selectControl);
selectControl.activate();

// 绘制要素
var drawControl = new OpenLayers.Control.DrawFeature(featureLayer, OpenLayers.Handler.Point);
map.addControl(drawControl);
drawControl.activate();

// 修改要素
modifyControl.activate();

var updatedFeatures = featureLayer.getFeaturesByAttribute("state", OpenLayers.State.UPDATE);

const pgp = require('pg-promise')();
const db = pgp('postgres://username:password@host:port/database');

// 将要素保存到数据库表中
db.none('INSERT INTO features (name, geometry) VALUES ($1, $2)', [feature.attributes.name, feature.geometry])
  .then(() => {
    console.log('要素保存成功');
  })
  .catch(error => {
    console.error('要素保存失败', error);
  });