html

<el-upload class="upload-demo" action="http://localhost:80" :limit='5' :auto-upload="false" :on-exceed='uploadOverrun' ref="upload" :http-request='submitUpload' :on-change='changeUpload'>
      <el-button size="small" type="primary">点击上传</el-button>
      <div slot="tip" class="el-upload__tip">只能上传jpg/png文件，且不超过500kb</div>
</el-upload>
<el-button @click = 'submitAssess'>提交到服务器</el-button>

js

uploadOverrun: function() {
                this.$message({
                    type: 'error',
                    message: '上传文件个数超出限制!最多上传5张图片!'
                });
            },
            changeUpload: function(file, fileList) {//预览图片
                this.fileList = fileList;
                this.$nextTick(
                    () => {
                        let upload_list_li = document.getElementsByClassName('el-upload-list')[0].children;
                        for (let i = 0; i < upload_list_li.length; i++) {
                            let li_a = upload_list_li[i].children[0];
                            let imgElement = document.createElement("img");
                            imgElement.setAttribute('src', fileList[i].url);
                            imgElement.setAttribute('style', "max-width:50%;padding-left:25%");
                            if (li_a.lastElementChild.nodeName !== 'IMG') {
                                li_a.appendChild(imgElement);
                            }
                        }
                    })
            },
            submitUpload: function(content) {//自定义的上传图片的方法
                //1. 创建formData 利用AXIOS传递
                let formData = new FormData;
                formData.append('file', content.file);
                let config = {
                    'Content-Type': 'multipart/form-data'
                }
                let var_this = this;
                axios.post('/Index/upload', formData, config)
                    .then(function(response) {
                        if (!response.data.success) {
                            var_this.$message({
                                message: response.data.message,
                                type: 'error'
                            });
                        }
                    })
                    .catch(function(error) {
                        console.log(error);
                    })
            },
submitAssess: function() {this.$refs.upload.submit(); //调用submit方法
             //其他业务代码。
         }

php

public function upload(){
        //上传文件
        if(!empty($_FILES)) {
            if(!empty($_SESSION)){
                //拼接路径
                $filePathArr = explode('/', $_SERVER['SCRIPT_FILENAME']);
                array_pop($filePathArr);
                $filePath = implode('/', $filePathArr);
                $filePath .= '/static/upload/';
                if(!is_dir($filePath)){ //创建文件夹
                    mkdir($filePath);
                }
                $filePath .= Session::get('user').'-->'.md5(time()).$_FILES['file']['name'];
                if(move_uploaded_file($_FILES["file"]["tmp_name"],$filePath)){
                    $filePath = str_replace($_SERVER['CONTEXT_DOCUMENT_ROOT'],"",$filePath);
                    //其他业务代码.我在制作此处时，我先将图片存入数据库
                    
                }else{
                    $data = returnData(false,'对不起,操作失败!请稍候再试!');
                }
            }else{
               $data = returnData(false,'请登录后再试!');
            }
            echo json_encode($data);
        }
 
    }

原文出自：https://blog.csdn.net/a12541254/article/details/79187130