微信小程序中定位城市

var QQMapWX = require('qqmap-wx-jssdk.js');
var qqmapsdk;
const getCurCity = function (callback) {
  qqmapsdk = new QQMapWX({
    key: '*****************'
  });
  wx.getLocation({
    type: 'wgs84',
    success: function (res) {
      var latitude = res.latitude
      var longitude = res.longitude
      console.log('latitude')
      console.log('longtitude')
      qqmapsdk.reverseGeocoder({
        location: {
          latitude: latitude,
          longitude: longitude
        },
        success: function (res) {
          var city=res.result.ad_info.city;
          if(city.endsWith('市'))
          {
            city=city.substr(0,city.length-1);
          }
          if(callback)
          {
            callback(city);
          }
        }
      });
    }
  })
}