这篇文章主要向大家介绍笔记：el-upload中，before-upload中的方法返回false时，会触发on-remove绑定的事件,主要内容包括基础应用、实用技巧、原理机制等方面，希望对大家有所帮助。
场景
表单编辑时，要求删除上传的图片后重置某些状态，天然在on-remove中的事件写。然而，当修改上传的图片，且图片不合规时，before-uoload中天然的返回了false，还触发了on-remove事件，可是界面上的图片是在的，不须要你重置状态！！！spa
个人办法
通过对on-remove对应参数的打印，发现回调中的file参数有个status，若是是在before-upload中就被过滤了，就是ready，若是已经上传成功了去点击删除，status是success，就他了。
onRemove(file,fileList){
if(file.status == 'success'){
//删除后改变某些状态的代码
}
if(file.status == 'ready'){
//这里应该就是before-upload中返回false时的状况了，还有没有别的状况，未知
}
}
图片上传示例：elementUI组件
imageUpload.vue 组件
<template>
<div v-loading="isLoading">
<el-upload
ref="upload"
action="/jpark-center-mgr/api/jsis/upload/upload2oss"
multiple
:limit="3"
:headers="headers"
list-type="picture-card"
:on-remove="handleRemove"
:on-preview="handlePictureCardPreview"
:on-exceed="handleExceed"
:on-success="handleSuccess"
:on-error="handleError"
:before-upload="beforeAvatarUpload"
:file-list="fileList"
>
<i slot="default" class="el-icon-plus"></i>
<div class="el-upload__tip" slot="tip">只能上传{{supportFileExt}}文件，最多上传3张图片，且每张图片不超过5MB</div>
</el-upload>
<el-dialog :visible.sync="dialogVisible1" append-to-body>
<img width="100%" :src="dialogImageUrl" alt="">
</el-dialog>
</div>
</template>
<script>
import jportalCommon from '@/jportal-common-update'
let userStorageService = jportalCommon.userStorageService
export default {
props: {
// limit: {
// type: Number,
// default: 10,
// required: false
// },
// requestUrl: {
// type: String,
// default: "/jpark-center-mgr/api/jsis/upload/upload2oss",
// required: false
// },
// supportFileExt: {
// type: String,
// default: "jpg/jpeg/png/doc/docx/xls/xlsx/rar/zip",
// required: false
// },
// limitFileSize: {
// type: Number,
// default: 10,
// required: false
// },
fileList: {
type: Array,
default: function () {
return []
},
required: true
}
},
data() {
return {
isLoading: false,
//上传文件
headers: {
'orgCode': userStorageService.getUser().orgCode,
'personId': userStorageService.getUser().personId,
'personName': encodeURIComponent(userStorageService.getUser().personName),
'jsToken': userStorageService.getToken().jsToken,
'jsCurAccNo': userStorageService.getToken().jsCurAccNo
},
// 上传图片
dialogImageUrl: '',
dialogVisible1: false,
supportFileExt: "jpg/jpeg/png",
limitFileSize: 5, // 5M
// fileList: [
// // {url: 'https://fuss10.elemecdn.com/3/63/4e7f3a15429bfda99bce42a18cdd1jpeg.jpeg?imageMogr2/thumbnail/360x360/format/webp/quality/100'},
// // {url: 'https://fuss10.elemecdn.com/3/63/4e7f3a15429bfda99bce42a18cdd1jpeg.jpeg?imageMogr2/thumbnail/360x360/format/webp/quality/100'}
// ],
}
},
methods: {
// 上传图片
handleRemove(file, fileList) {
// console.log('删除图片', file)
if (file.status == 'success') { // 防止before-upload返回false时，会删除前一个上传成功的图片
let url = file.response?file.response.respData.url:file.url
this.fileList.splice(this.fileList.findIndex(item => item.url == url), 1)
this.$emit("update:fileList", this.fileList);
}
if(file.status == 'ready'){
//这里应该就是before-upload中返回false时的状况了，还有没有别的状况，未知
}
// console.log('删除完后剩下的图片', this.fileList)
},
handlePictureCardPreview(file) {
this.dialogImageUrl = file.url;
this.dialogVisible1 = true;
},
handleDownload(file) {
console.log(file);
},
handleExceed(files, fileList) {
this.$message({
type: 'warning',
message: '最多只能上传3个文件'
})
},
handleSuccess(res, file, fileList) {
this.isLoading = false;
// var temp = {};
// temp.name = file.name;
// temp.size = Math.round(file.size / 1024);
this.fileList.push({url: res.respData.url});
// console.log('this.fileList',this.fileList)
this.$emit("update:fileList", this.fileList);
this.$message({
type: 'success',
message: '文件上传成功'
});
},
handleError(e, file) {
this.isLoading = false;
this.$message({
type: 'error',
message: e
});
},
//上传文件对应的函数
beforeAvatarUpload(file) {
const surportExt = "."+this.supportFileExt.split("/").join("/.")
const isRuleFile = file && file.name && surportExt.indexOf(file
.name.substring(file.name.lastIndexOf(".")).toLowerCase()) != -1;
const isLt10M = file.size / 1024 / 1024 < this.limitFileSize;
if (!isRuleFile) {
this.$message.error('请按指定文件格式上传!');
}
if (!isLt10M) {
this.$message.error('上传文件大小不能超过 '+this.limitFileSize+'MB!');
}
if (isRuleFile && isLt10M) {
this.isLoading = true;
}
return isRuleFile && isLt10M;
},
clearFiles() {
this.fileList = [];
this.$refs.upload.clearFiles();
}
},
watch: {
},
mounted() {
}
}
</script>
<style scoped>
.a-link {
color: #030303;
text-decoration: none;
}
.a-link:hover {
color: #4E84FE;
}
.upload-button {
width: 90px;
height: 90px;
background: rgba(78, 132, 254, 1);
border-radius: 4px;
cursor: pointer;
float: left;
line-height: 25px;
padding-top: 20px;
}
.upload-tip {
float: right;
width: 350px;
margin-left: 20px;
margin-top: 50px;
text-align: left;
line-height: 20px;
}
.icon-upload {
width: 14px;
height: 16px;
}
.icon-files {
width: 15px;
height: 17px;
cursor: pointer;
}
.content-font {
color: #030303;
font-weight: 400;
}
</style>
父组件中引入子组件：
<image-upload :fileList.sync="fileList"></image-upload> // .sync 是为了方便父子组件同时修改值// {url: 'https://fuss10.elemecdn.com/3/63/4e7f3a15429bfda99bce42a18cdd1jpeg.jpeg?imageMogr2/thumbnail/360x360/format/webp/quality/100'}
...
data () {
return {
fileList: [ // 编辑时候默认传的数据格式
// {url: 'https://fuss10.elemecdn.com/3/63/4e7f3a15429bfda99bce42a18cdd1jpeg.jpeg?imageMogr2/thumbnail/360x360/format/webp/quality/100'},
]
}
}
原文地址：https://juejin.im/post/5daff2ede51d4524c118081f
before-upload中返回false时