1.先使用微信自帶方法wx.getLocation去獲取經緯度。

wx.getLocation({
      type: 'wgs84',   //預設為 wgs84 返回 gps 座標，gcj02 返回可用於 wx.openLocation 的座標 
      success: function (res) {
        // success  
        var longitude = res.longitude
        var latitude = res.latitude
        _self.loadCity(longitude, latitude)
        console.log(longitude, latitude)
      }
    })
 

2.

loadCity: function (longitude, latitude) {
    var _self = this;
    wx.request({
      url: 'https://restapi.amap.com/v3/geocode/regeo',
      data: {
        key: '你的高德key',
        location: longitude + "," + latitude,
        extensions: "all",
        s: "rsx",
        sdkversion: "sdkversion",
        logversion: "logversion"

      },
      success: function (res) {
        _self.setData({
          city: res.data.regeocode.addressComponent.city
        })
        // console.log(res.data.regeocode.addressComponent.city);
      },
      fail: function (res) {
        console.log('獲取地理位置失敗')
      }
    })
  }