"vue": "^2.5.2",
"element-ui": "^2.2.1",

<el-upload
    action="http://mt.cn:3355/backend/config/uploadImg"
    list-type="picture-card"
    :file-list="themePictures"
    :data="themeData"
    :on-success="themeSuccess"
    :on-remove.self="removeTheme"
    :on-error="uploadError"
    :before-upload="beforeUpload">
    <i class="el-icon-plus"></i>
</el-upload>

removeTheme(file, fileList) {
    req_removeTheme({id:file.id}).then(res => {
        this.$message.success('删除成功')
    })
},
beforeUpload(file) {
    const isMatch = file.type === 'image/jpeg' || file.type === 'image/jpg' || file.type === 'image/png' || file.type === 'image/gif' || file.type === 'image/bmp'
    const isLt2M = file.size / 1024 / 1024 < 1

    if (!isMatch) {
        this.$message.error('图片格式不匹配')
    }
    if (!isLt2M) {
        this.$message.error('上传头像图片大小不能超过 1MB!')
    }
    return isMatch && isLt2M
},