VX小程序实现区域转图片预览

方法一

1、安装插件 wxml2canvas

npm install --save wxml2canvas

2、类型

// 小程序页面
let data={list:[{type:'wxml',class:'.test_center .draw_canvas',limit:'.test_center',x:0,y:0}]
}

3、数据结构

let testData=[{PageIndex:1,ImageUrl:"https://minio.23544.com:9010/mk-sys-test/origin-paper/432531489095806/2023-06-26-15-42-38/9d43c15bb1834cacb0a8900b5e45dfb2/1.jpg",Height:1680.0,Width:1200.0,Questions:[{"QuestionNum":"1-2","X":140.00000450195313,"Y":515.989620895996,"Width":149.77778,"Height":54.77778,"score":1.00,"totalScore":2.00},{"QuestionNum":"1111","X":113.10765335144043,"Y":756.3195006567382,"Width":799.77778,"Height":199.77778,"score":0.0,"totalScore":0.0},{"QuestionNum":"2222","X":100.0000025946045,"Y":822.2222792822265,"Width":799.77778,"Height":199.77778,"score":0.0,"totalScore":0.0},{"QuestionNum":"12","X":95.9895980078125,"Y":1260.989620895996,"Width":1022.77778,"Height":305.77778,"score":1.00,"totalScore":14.00},]},{PageIndex:1,ImageUrl:"https://minio.23544.com:9010/mk-sys-test/origin-paper/432531489095806/2023-06-26-15-42-38/9d43c15bb1834cacb0a8900b5e45dfb2/1.jpg",Height:1680.0,Width:1200.0,Questions:[{"QuestionNum":"1-2","X":140.00000450195313,"Y":515.989620895996,"Width":149.77778,"Height":54.77778,"score":1.00,"totalScore":2.00},{"QuestionNum":"1111","X":113.10765335144043,"Y":756.3195006567382,"Width":799.77778,"Height":199.77778,"score":0.0,"totalScore":0.0},{"QuestionNum":"2222","X":100.0000025946045,"Y":822.2222792822265,"Width":799.77778,"Height":199.77778,"score":0.0,"totalScore":0.0},{"QuestionNum":"12","X":95.9895980078125,"Y":1260.989620895996,"Width":1022.77778,"Height":305.77778,"score":1.00,"totalScore":14.00},]}]

4、页面引用

<template><canvas canvas-id="canvas1" class="test_center"></canvas>
</template><script setup>
import Wxml2Canvas from 'wxml2canvas';
const onclicks=()=> {person.drawImage = new Wxml2Canvas({width: 340,height: 210,element: 'canvas1',background: '#f0f0f0',finish(url) {console.log(7777,url)uni.previewImage({// 需要预览的图片链接列表urls: [url],// 为当前显示图片的链接/索引值current: url,// 图片指示器样式	indicator:'default',// 是否可循环预览loop:false});},error (res) {}});let data = {list: [{type: 'image',x: 0,y: 0,url: person.itemExam.ImageUrl,style: {width: person.itemExam.Width*person.scaleWidth,height: person.itemExam.Height*person.scaleWidth,border: '0 solid #aaaaaa',boxShadow: '10 20 20 rgba(0, 0, 0, 0.4)'}}]}person.itemExam.Questions.forEach((quest,itIndex)=>{data.list.push({type: 'text',text: quest.score,x: quest.X*person.scaleWidth,y: quest.Y*person.scaleWidth,style: {textAlign: 'right',width: quest.Width*person.scaleWidth-40,height: quest.Height*person.scaleWidth-40,fontSize: 16,color: 'red',border: '0px solid red',padding: '6px 40px 0 0'}})data.list.push({type: 'text',text: '  /'+quest.totalScore,x: quest.X*person.scaleWidth,y: quest.Y*person.scaleWidth,style: {textAlign: 'right',width: quest.Width*person.scaleWidth-6,height: quest.Height*person.scaleWidth-6,fontSize: 16,color: 'blue',border: '1px solid red',padding: '6px 6px 0 0'}})})person.drawImage.draw(data);
}
</script>