微信小程序 实现路线规划

route(fromlatlng, tolatlng) {// 路线规划
var that = this;
  let routeparam = {
    from: fromlatlng,//起点经纬度，小数点后不超过6位，40.056878,116.30815
    to: tolatlng,//终点经纬度，小数点后不超过6位，
    key: 'DASC431-Q321EO-TNEW5-12REQ-Q231I6-FSFDS21',//腾讯地图开放平台申请key
  };
  uni.request({
    url: 'https://apis.map.qq.com/ws/direction/v1/driving',
    data: routeparam,
    header: {
      "content-type": "application/json"
    },
    method: 'GET',
    success(ret) {
		if(ret.data.status==0){
			// console.log(ret.data.result.routes[0].polyline)
			//从结果中取出路线坐标串
			var coors = ret.data.result.routes[0].polyline, pl = [];
			//坐标解压（返回的点串坐标，通过前向差分进行压缩，因此需要解压）
			var kr = 1000000;
			for (var i = 2; i < coors.length; i++) {
			  coors[i] = Number(coors[i - 2]) + Number(coors[i]) / kr;
			}
			//将解压后的坐标生成LatLng数组
			for (var i = 0; i < coors.length; i += 2) {
			  pl.push({
				  latitude:coors[i],
				  longitude:coors[i+1]
			  });
			}
			let ps = {
				points: pl,
				dottedLine: false,
				width: 5,
				color: "#2B97FD"
			}
			that.polyline = that.polyline.concat(ps);//绘制轨迹线
		}
    },
    fail(data) {
      fail(data);
    }
  });
},