之前做的图片上传需求是自动上传并且只带header，这次需要传参数给后台并且格式是formData，非自动上传，而是点击按钮上传，让我琢磨了半天。
需求图片如下
html代码如下
<div class="img-list"><div class="img" v-for="(item,index) in imgList" :key="index"><img :src="item" alt=""><div><span></span><i @click="deleteImg(item)"></i></div></div><div style="clear:both;"></div></div><div class="upload-btn"><div class="upload-left"><input type="text" v-model="fileName" placeholder="请选择文件"><el-uploadclass="upload-demo":action="global":headers="headers":show-file-list="false":auto-upload="false"ref="upload":data="resData":on-change="imgBroadcastChange":onSuccess="uploadSuccess"><el-button size="small" type="primary" class="file-btn"><i class="file-icon"></i> </el-button></el-upload></div><div class="upload-rig"><el-button @click="startUpload()">开始上传</el-button></div><div style="clear:both;"></div></div>
:auto-upload="false" 取消自动上传，:headers="headers"，
this.headers = {
"Content-Type": "multipart/form-data"
};设置header
js效果实现如下：
imgBroadcastChange(file, fileList){// debuggerthis.file = file.raw;this.fileName = file.name;},uploadSuccess(res, file) {},startUpload(){this.resData = {uid: localStorage.getItem("uid"),//用户登录之后服务器返回的用户唯一uidtoken: localStorage.getItem("token"),//用户登录之后服务器返回的标识用户的token，这两个值有的没有的可以不加action:"uploadStationPictureUrl",station_id:this.imgStationId,};const formData = new FormData();formData.append("uid", this.resData.uid);formData.append("token", this.resData.token);formData.append("action", this.resData.action);formData.append("station_id", this.resData.station_id);formData.append('file', this.file);this.$api({method: "post",url: "/api.php/DeviceManage/index",data: formData,}).then(su => {if (su.data.code == 1) {this.$TyMessage.success("上传成功");this.imgList.push(su.data.picture_url);} else if (su.data.code == 300) {this.$router.push("/login");this.$TyMessage.error(su.data.message);} else {this.$TyMessage.error(su.data.message);}}).catch(err => {});},
在change函数中把file.raw存储下来，用于点击上传图片的时候传给后台，
const formData = new FormData();formData.append("uid", this.resData.uid);formData.append("token", this.resData.token);formData.append("action", this.resData.action);formData.append("station_id", this.resData.station_id);formData.append('file', this.file);
将数据格式转换成formData格式。
