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这两天接到一个需求，是通过百度生成的轨迹制作成一个图片，好废话不多说，上干货

注释：这里我是用react编写的，不过代码逻辑都一样，看的懂就会搬运，不懂出可以留言，我会及时回复，每天每时都在

全部代码

import React, { useEffect } from 'react'
declare const BMapGL: any;
import html2canvas from 'html2canvas'
let bmap: any;
const Map = () => {
  const downLoad = (png: any) => {
    //创建一个a标签
    const a = document.createElement('a')
    //指定下载文件名称
    a.href = png;
    a.download = '截图'
    //a 标签 需要点击触发。所以强制给他分派一个点击事件
    //创建一个鼠标事件
    const event = document.createEvent("MouseEvents")
    // 初始化鼠标事件
    event.initMouseEvent("click", true, false, window, 0, 0, 0, 0, 0, false, false, false, false, 0, null)
    // 指定元素对象触发事件
    a.dispatchEvent(event)
  };
  const screenShot = () => {
    const element: any = document.getElementById('container')
    const options = {
      useCORS: true,
      // preserveDrawingBuffer: true,
      //foreignObjectRendering: true,
      allowTaint: true,
    };

    html2canvas(element, options).then(canvas => {
      const png = canvas.toDataURL("image/png") //拿到截图后转换为png图片
      const img = document.createElement('img')
      img.setAttribute('src', png)
      window.document.body.appendChild(img) //将png图片添加到页面验证
      console.log('png:', png)
      downLoad(png)
    })
  };
  useEffect(() => {
    bmap = new BMapGL.Map("container");
    const point = new BMapGL.Point(116.404, 39.915);
    // bmap.centerAndZoom(point, 15);
    bmap.enableScrollWheelZoom(true);
    bmap.centerAndZoom(new BMapGL.Point(116.404, 39.915), 11);

    const p1 = new BMapGL.Point(116.301934, 39.977552);
    const p2 = new BMapGL.Point(116.508328, 39.919141);

    const driving = new BMapGL.DrivingRoute(bmap, { renderOptions: { map: bmap, autoViewport: true } });
    driving.search(p1, p2);
  }, [])
  return (
    <div style={{ width: "100%", height: "100%" }}>
      <button onClick={screenShot}>下载</button>
      {/* <div id="r-result">请输入:<input type="text" id="suggestId" style={{ width: "200px" }} /></div> */}
      <div id="container" style={{ width: "100%", height: "100%" }}></div>
    </div>
  )
}

export default Map

该代码会展示一个空白的地图

在index.htlm文件中加入改代码，用来解决空白问题

<script>

  HTMLCanvasElement.prototype.getContext = function (origFn) {
      return function (type, attributes) {
        if (type === 'webgl') {
          attributes = Object.assign({}, attributes, {
            preserveDrawingBuffer: true,
          });
        }
        return origFn.call(this, type, attributes);
      };
    }(HTMLCanvasElement.prototype.getContext);
</script>

流程

一、展示地图

1、在根文件index.html中引入百度地图

  <script type="text/javascript" src="http://api.map.baidu.com/api?v=1.0&type=webgl&ak=你的key"></script>

2、展示地图并显示轨迹

由于我这边用的时ts的语法，用使用要仔细观看

import React, { useEffect } from 'react'
declare const BMapGL: any;
let bmap: any;
const Map = () => {

  useEffect(() => {
    bmap = new BMapGL.Map("container");
    const point = new BMapGL.Point(116.404, 39.915);
    bmap.centerAndZoom(new BMapGL.Point(116.404, 39.915), 11);
    bmap.enableScrollWheelZoom(true);
    const p1 = new BMapGL.Point(116.301934, 39.977552);
    const p2 = new BMapGL.Point(116.508328, 39.919141);
    const driving = new BMapGL.DrivingRoute(bmap, { renderOptions: { map: bmap, autoViewport: true } });
    driving.search(p1, p2);
  }, [])
  return (
    <div style={{ width: "100%", height: "100%" }}>
      {/* <button onClick={screenShot}>下载</button> */}
      {/* <div id="r-result">请输入:<input type="text" id="suggestId" style={{ width: "200px" }} /></div> */}
      <div id="container" style={{ width: "100%", height: "100%" }}></div>
    </div>
  )
}

export default Map

效果图：

二、开始制作百度地图图片

1、首先下载一个第三方包html2canvas

npm i html2canvas  / yarn add html2canvas

2、我们需要在index.htlm文件中修改这个包在展示地图的时候空白问题

<script>

  HTMLCanvasElement.prototype.getContext = function (origFn) {
      return function (type, attributes) {
        if (type === 'webgl') {
          attributes = Object.assign({}, attributes, {
            preserveDrawingBuffer: true,
          });
        }
        return origFn.call(this, type, attributes);
      };
    }(HTMLCanvasElement.prototype.getContext);
</script>

3、我们可以制作一个点击按钮，给他加点击事件，到这差不多就结束了，点击按钮就可以下载图片了

  const downLoad = (png: any) => {
    //创建一个a标签
    const a = document.createElement('a')
    //指定下载文件名称
    a.href = png;
    a.download = '截图'
    //a 标签 需要点击触发。所以强制给他分派一个点击事件
    //创建一个鼠标事件
    const event = document.createEvent("MouseEvents")
    // 初始化鼠标事件
    event.initMouseEvent("click", true, false, window, 0, 0, 0, 0, 0, false, false, false, false, 0, null)
    // 指定元素对象触发事件
    a.dispatchEvent(event)
  };
  const screenShot = () => {
    const element: any = document.getElementById('container')
    const options = {
      useCORS: true,
      // preserveDrawingBuffer: true,
      //foreignObjectRendering: true,
      allowTaint: true,
    };

    html2canvas(element, options).then(canvas => {
      const png = canvas.toDataURL("image/png") //拿到截图后转换为png图片
      const img = document.createElement('img')
      img.setAttribute('src', png)
      window.document.body.appendChild(img) //将png图片添加到页面验证
      console.log('png:', png)
      downLoad(png)
    })
  };

下载下来的效果图（备注：这个是通过公司的经纬度数据产生的数据）

到这差不多就结束

完美结束，完结撒花