element + vue 实现背景图片设置

<template>
  <div>
    <el-row>
      <el-col :span="3">
        <el-upload
          action="#"
          list-type="picture-card"
          :file-list="fileList"
          :on-preview="onPreview"
          :limit="limit"
          :class="{ disabled: fileList.length === limit }"
          :on-remove="onRemove"
          :on-change="onChange"
          :before-upload="beforeUpload"
          :http-request="httpRequest"
        >
          <i class="el-icon-plus" />
        </el-upload>
      </el-col>
      <el-col :span="10">
        <el-button size="medium" type="primary" plain style="width: 168px"
          >提交</el-button
        ><br /><br />
        <el-button size="medium" type="primary" style="width: 168px" plain
          >取消</el-button
        ><br /><br />
        <el-button size="medium" type="primary" plain
          >恢复当前的皮肤背景</el-button
        >
      </el-col>
    </el-row>
    <el-row style="font-size: 12px">
      只能上传2张jpg/png文件，每张且不超过500Kb
    </el-row>
    <br />
    预设背景图:
    <br />
    <br />
    <div class="demo-image__preview">
      <div class="previewImage">
        <el-image
          style="width: 148px; height: 148px; margin-right: 2px"
          v-for="(item, index) in imageUrls"
          :key="index"
          :src="item.url"
          @click.native="selectFn(item.url)"
        >
        </el-image>
      </div>
    </div>
    <!-- 图片预览 -->
    <el-dialog title="预览" :visible.sync="showImgDialog">
      <img :src="showImgUrl" style="width: 100%" alt="" />
    </el-dialog>
  </div>
</template>
<script>
export default {
  name: "ImageUpload",
  props: {
    // 限定只能上传几个
    limit: {
      type: Number,
      default: 1,
    },
  },
  data() {
    return {
      showImgUrl: "",
      showImgDialog: false,
      fileList: [],
      currrentUid: null, // 当前正在上传的uid
      percentageNum: 0,
      percentageShow: false,
      url: "https://fuss10.elemecdn.com/e/5d/4a731a90594a4af544c0c25941171jpeg.jpeg",
      //   srcList: [
      //     "https://fuss10.elemecdn.com/8/27/f01c15bb73e1ef3793e64e6b7bbccjpeg.jpeg",
      //     "https://fuss10.elemecdn.com/1/8e/aeffeb4de74e2fde4bd74fc7b4486jpeg.jpeg",
      //   ],
      // 预览图片的地址 url
      imageUrls: [
        {
          url: "https://fuss10.elemecdn.com/1/8e/aeffeb4de74e2fde4bd74fc7b4486jpeg.jpeg",
        },
        {
          url: "https://fuss10.elemecdn.com/1/8e/aeffeb4de74e2fde4bd74fc7b4486jpeg.jpeg",
        },
        {
          url: "https://fuss10.elemecdn.com/8/27/f01c15bb73e1ef3793e64e6b7bbccjpeg.jpeg",
        },
        {
          url: "https://fuss10.elemecdn.com/1/8e/aeffeb4de74e2fde4bd74fc7b4486jpeg.jpeg",
        },
        {
          url: "https://fuss10.elemecdn.com/1/8e/aeffeb4de74e2fde4bd74fc7b4486jpeg.jpeg",
        },
        {
          url: "https://fuss10.elemecdn.com/8/27/f01c15bb73e1ef3793e64e6b7bbccjpeg.jpeg",
        },
        {
          url: "https://fuss10.elemecdn.com/8/27/f01c15bb73e1ef3793e64e6b7bbccjpeg.jpeg",
        },
        {
          url: "https://fuss10.elemecdn.com/8/27/f01c15bb73e1ef3793e64e6b7bbccjpeg.jpeg",
        },
        {
          url: "https://fuss10.elemecdn.com/8/27/f01c15bb73e1ef3793e64e6b7bbccjpeg.jpeg",
        },
        {
          url: "https://fuss10.elemecdn.com/8/27/f01c15bb73e1ef3793e64e6b7bbccjpeg.jpeg",
        },
      ],
    };
  },
  methods: {
    selectFn(url) {
      console.log(url);
      console.log(this.fileList);
      this.fileList = [
        {
          status: "ready",
          name: "gdnMq.jpg",
          size: 15097,
          percentage: 0,
          uid: 1676478291934,
          raw: "[object File]",
          url: url,
        },
      ];
      console.log(this.fileList);
    },
    // handleAvatarSuccess(res, file) {
    //   console.log(111);
    //   this.imageUrl = URL.createObjectURL(file.raw);
    // },
    // 图片预览的时候
    onPreview(file) {
      //   console.log(file);  blob文件 图片暂时的url
      this.showImgUrl = file.url;
      this.showImgDialog = true;
    },
    // 图片删除的钩子
    onRemove(file, fileList) {
      //   console.log(fileList);
      // file是删除的那个图片信息，fileList是剩余的最新的fileList
      this.fileList = fileList;
    },
    // 文件改变的时候====> 1. 添加文件    2. 上传成功或失败都调用
    onChange(file, fileList) {
      // ready 的时候，fileList其实多了一个元素【本地预览的地址】
      // fail  的时候，fileList会把刚才没成功的移除了
      // success 的时候， fileList 多了个元素 【真实的线上地址，临时预览图片】
      //   console.log("文件改变的时候", file, file.status);
      this.fileList = fileList; ///  有没有这句代码的区别在于【是否有上传的方块】
    },
    // 上传之前的检查钩子 用于校验
    beforeUpload({ size, type, uid }) {
      // 检测大小
      const maxSize = 10; // 10 M
      if (size > 1024 * 1024 * maxSize) {
        this.$message.warning(`体积不允许超过${maxSize}M`);
        return false;
      }
      // 检测类型
      const types = ["image/jpeg", "image/gif", "image/bmp", "image/png"];
      if (!types.includes(type)) {
        this.$message.warning(`格式不正确`);
        return Promise.reject();
      }
      this.currrentUid = uid;
      this.percentageShow = true; // 此时进度条结束
      // 通过就是true
      return true;
    },
    // beforeAvatarUpload(file) {
    //   const isJPG = file.type === "image/jpeg";
    //   const isLt2M = file.size / 1024 / 1024 < 2;
    //   if (!isJPG) {
    //     this.$message.error("上传头像图片只能是 JPG 格式!");
    //   }
    //   if (!isLt2M) {
    //     this.$message.error("上传头像图片大小不能超过 2MB!");
    //   }
    //   return isJPG && isLt2M;
    // },
    // 覆盖默认的上传行为
    httpRequest(data) {
      console.log("要上传的文件信息", data.file);
      // 发起上传文件的请求操作 【自己服务器的还是用第三方的COS，根据项目情况】
      //   let fd = new FormData();
      //   fd.append(xx, xxx);
    },
  },
};
</script>
<style  lang="scss" >
.disabled {
  .el-upload {
    display: none;
  }
}
.previewImage {
  width: 750px;
  height: 298px;
  background-color: pink;
}
</style>