关于前端:elementui-elupload-上传图片

<div class="company-img" :class="{'active' : imageUrl}">                        <el-image :src="imageUrl" :preview-src-list="[imageUrl]" style="width:162px;height:60px;"></el-image></div>                    <el-upload class="avatar-uploader" action="https://jsonplaceholder.typicode.com/posts/"                               :show-file-list="false" :auto-upload="false" :on-change="uploadChange" :limit="limitNum" ref="upload">                        <div class="click-upload">                            <img src="@/assets/images/update.png" alt="" style="height:27px;margin-top:15px;margin-left: 19px;">                            <p>点击上传</p>                        </div>                    </el-upload> data () {        return {            imageUrl: '', // 图片地址        },async uploadChange (file) {            const isPic = file.raw.type === 'image/jpeg' || file.raw.type === 'image/jpg' || file.raw.type === 'image/png';            // 文件不可大于300kb            // const isLt300K = file.size / 1024 / 1024 < 0.3;            const isLt300K = file.size / 1024 / 2000 <= 1;            if (!isPic) {                this.$message.error('上传头像图片仅反对 PNG, JPEG, JPG 格局!');                this.$refs.upload.clearFiles(); // 如果文件类型不符  则革除该数据                return;            }            if (!isLt300K) {                this.$message.error('上传头像图片大小不能超过 300kb!');                this.$refs.upload.clearFiles();                return;            }            // 只能上传一张图片            if (this.$refs.upload.uploadFiles.length > 1) {                this.$refs.upload.uploadFiles.pop();            }            this.imageUrl = URL.createObjectURL(file.raw);            var formData = new FormData();            formData.append('logoFile', file.raw); // 传参            formData.append('tenantId', this.userInfo.frontTenantId);            await this.$api.EnterpriseSettingsManagement.updateLogoFile(formData);            this.$message.success('信息批改胜利');        }