vue.js3:分割图片为四宫格九宫格等形式(vue@3.2.37)

<template>
<div>
  <div style="width:800px;margin: auto;display: flex;flex-direction: column;">
    <div>请选择上传图片:
      <input type="file" id="back" ref="backfile" accept="image/*" @change="handleFile" /></div>

    <div id="imgContainer" <br>style="position: relative;margin-left:150px;margin-top:10px;width:500px;height:500px;overflow: hidden;background: lightgray;" >
      <img id="img" :src="imgSrc" style="" />
    </div>

    <div style="margin-left:150px;">
      <template v-for='(items, index) in imgList' :key="index">
        <div style="font-size:0;">
        <template v-for='(itemOne, indexOne) in items' :key="indexOne">

          <img :src="itemOne" style="width:200px;display: block;float:left;margin-left: 5px;margin-top: 5px;" />

          <!--{{itemOne}}-->
        </template>
        </div>
      </template>
    </div>

    <div id="dpiBtn" style="display: none;">
      <input type="button" value="分割图片" @click="split" />
      <input type="button" value="打包下载图片" @click="downZip" style="margin-left: 20px;" />
    </div>
  </div>
</div>
</template>

<script>
import {ref} from "vue";

export default {
  name: "ImageSplit",
  setup() {
    //图片的原宽高
    const imgWidth = ref(0);
    const imgHeight = ref(0);
    //图片内容
    const imgSrc = ref("");
    //选中的图片文件，保存在数组中
    const imgFile = ref();
    const roundMax = ref(0);
    //选中图片后的处理
    const handleFile = () => {
      let filePaths = window.event.target.files;
      //清空原有缩略图
      if (filePaths.length === 0) {
        //未选择，则返回
        return
      }
      //把新选中的图片加入数组
      imgFile.value = filePaths[0];
      imgSrc.value = URL.createObjectURL(imgFile.value);

      let reader = new FileReader();
      reader.readAsDataURL(imgFile.value);

      reader.onload = () =>{
        //显示图片
        imgSrc.value = reader.result;
        //得到宽高
        let img = new Image();
        img.src= reader.result;
        img.onload = () => {
          //保存宽高
          imgWidth.value = img.width;
          imgHeight.value = img.height;

          if (img.width >= img.height) {
            roundMax.value = img.height/2;
            let rate = 500 / img.width;

            let left = (500-img.width) / 2;
            let top = (500 -img.height) / 2;

            let styleStr =  'display: inline-block;position:absolute;transform:scale('+rate+');left:'+left+'px;display: block;top:'+top+'px;';
            document.getElementById('img').style =  styleStr;
          } else {
            roundMax.value = img.width/2;
            let rate = 500 / img.height;

            let left = (500-img.width) / 2;
            let top = (500 -img.height) / 2;

            let styleStr = 'display: inline-block;position:absolute;transform:scale('+rate+');left:'+left+'px;display: block;top:'+top+'px;';
            document.getElementById('img').style =  styleStr
          }
          //显示btn
          document.getElementById('dpiBtn').style.display="";
        }
      }
    }
      const imgList = ref([]);
      //行数
      const rows = ref(2);
      //列数
      const columns = ref(2);

      //拆分图片
      const split = () => {
        var canvas = document.createElement("canvas");
        canvas.width = imgWidth.value;
        canvas.height = imgHeight.value;
        let ctx = canvas.getContext('2d');
        let img = document.getElementById('img');
        ctx.drawImage(img, 0, 0, imgWidth.value, imgHeight.value);
        let list = getList(ctx);
        imgList.value = list;
        console.log(imgList.value);
      }

      //得到切割后的图片列表
      const getList = (ctx) => {
        let destWidth = ctx.canvas.width / columns.value;
        let destHeight = ctx.canvas.height / rows.value;
        let list = [];
        for (let i=0;i<rows.value;i++) {
            let listOne = [];
            for (let k=0;k<columns.value;k++) {
              console.log("i:"+i+";k:"+k);
              let url = getPart(ctx,k*destWidth,i*destHeight,destWidth,destHeight);
              listOne.push(url);
            }
            list.push(listOne);
        }
        return list;
      }
      //得到canvas的指定部分
      const getPart = (ctx,x,y,w,h) => {
        let canvas = document.createElement("canvas");
        canvas.width = w;
        canvas.height = h;
        console.log("x:"+x+";y:"+y+";w:"+w+";h:"+h);
        let data = ctx.getImageData(x,y,w,h);
        let context = canvas.getContext("2d");
        context.putImageData(data,0,0);
        return canvas.toDataURL("image/png",1);
      }

      return {
        handleFile,
        imgSrc,
        imgList,
        rows,
        columns,
        split,
      }
  }
}
</script>

<style scoped>

</style>