回答

首先登陆腾讯位置服务网站https://lbs.qq.com/

登陆后创建一个应用

勾选webserviceapi

并填写自己的微信小程序授权appid

提交后等待审核，审核通过后，就可以看到key了

wxml

<map id="map" style="width:100%;height:500px;" show-location="true" circles="{{circles}}" longitude="{{longitude}}" markers="{{markers}}" polyline="{{polyline}}" latitude="{{latitude}}" scale="14" ></map>

js代码

var coors;

Page({

    data: {
        longitude: 116.75498,
        latitude: 23.37228,
        polyline: [],

        markers: [

            {
                latitude: 23.362490,
                longitude: 116.715790,
                iconPath: "/images/my_marker.png", //图标路径
              
            },

            {
                latitude: 23.37228,
                longitude: 116.75498,
                iconPath: "/images/my_marker.png", //图标路径
            },
          
        ],

    },

    onLoad: function (options) {

        var that = this;

        wx.request({

            url: 'https://apis.map.qq.com/ws/direction/v1/driving/?from=23.362490,116.715790&to=23.37228,116.75498&output=json&callback=cb&key=申请的key'

                ,
            success: function (res) {

                coors = res.data.result.routes[0].polyline
                
                for (var i = 2; i < coors.length; i++) {

                    coors[i] = coors[i - 2] + coors[i] / 1000000

                }

                console.log(coors)

                //划线 

                var b = [];

                for (var i = 0; i < coors.length; i = i + 2) {

                    b[i / 2] = {
                        latitude: coors[i],
                        longitude: coors[i + 1]
                    };

                    console.log(b[i / 2])

                }

              
let markers=that.data.markers;
markers.push( {
    latitude: 23.373390,
    longitude: 116.716590,
    iconPath: "/images/no.png", //图标路径
    width:340,
    height:40,
    label:{
  

        content:"共"+ res.data.result.routes[0].distance/1000+"公里，大约需要"+res.data.result.routes[0].duration+"分钟",
        bgColor:"#ff9000",
        padding:"9px 20px",
        alpha:1,
        borderRadius:"50rpx",
display:"ALWAYS",
        color:"#ffffff",
        fontsize:14
    }
}
);
console.log(markers);
that.setData({
    markers:markers,
    polyline: [{
       
        points: b,
        color: "#a52a2a",
        width: 4,
        dottedLine: false
    }],

})     
            }

        })

    },

});

官方的webserviceapi接口文档地址：https://lbs.qq.com/service/webService/webServiceGuide/webServiceRoute

项目源码下载地址：map.zip