1.php部分（本例thinkphp5.1）：

  下载PHPExcel了扩展http://phpexcel.codeplex.com/

<?php
namespace app\admin\controller;

// 引入phpExcel
use Env;
use vendor\PHPExcel\PHPExcel;

class Upload
{
    //上传Excel  导入数据
    public function import(){
        include_once(Env::get('root_path').'vendor/PHPExcel/PHPExcel.php');
//        $objPHPExcel = new \PHPExcel();
        $file = request()->file('file');
        $info = $file->validate(['size'=>52428800])->move( '../public/uploads');
        if($info){
            $ext = $info->getExtension(); //获取文件后缀名
            if(!in_array($ext,['xlsx','xls'])){
                $msg=['code'=>-1,'msg'=>"文件格式有误"];
            }else{
                $path = $_SERVER['DOCUMENT_ROOT'].'/uploads/'.str_replace('\\', '/', $info->getSaveName());   //上传文件路径
                if (!file_exists($path)) {
                    $msg['res'] = -1;
                    $msg['msg'] = "上传文件丢失!" . $file->getError();
                }

                if ($ext == 'xlsx') {
                    $objReader = \PHPExcel_IOFactory::createReader('Excel2007');
                    $objPHPExcel = $objReader->load($path, 'utf-8');
                } elseif ($ext == 'xls') {
                    $objReader = \PHPExcel_IOFactory::createReader('Excel5');
                    $objPHPExcel = $objReader->load($path, 'utf-8');
                }

                $sheet = $objPHPExcel->getSheet(0);
                $highestRow = $sheet->getHighestRow(); // 取得总行数
//                $highestColumn = $sheet->getHighestColumn(); // 取得总列数
                $i = 0;
                $importRows = 0;
                $addData = [];
                for ($j = 2; $j <= $highestRow; $j++) {
                    $importRows++;
                    $realName = (string)$objPHPExcel->getActiveSheet()->getCell("A$j")->getValue();//需要导入的realName
                    $phone = (string)$objPHPExcel->getActiveSheet()->getCell("B$j")->getValue();   //需要导入的phone
                    $company = (string)$objPHPExcel->getActiveSheet()->getCell("C$j")->getValue(); //需要导入的company
                    $job = (string)$objPHPExcel->getActiveSheet()->getCell("D$j")->getValue();     //需要导入的job
                    $email = (string)$objPHPExcel->getActiveSheet()->getCell("E$j")->getValue();   //需要导入的email

                    $addData[] = ['name'=>$realName,'tel'=>$phone,'company'=>$company,'job'=>$job,'email'=>$email];
                    $i++;
                }
                halt($addData);  //打印数据
                //数据写入数据库
                $result = model('')->insertAll($addData);
                if($result){
                    $msg = ['code'=>0,'msg'=>'导入数据成功！'];
                }else{
                    $msg = ['code'=>-1,'msg'=>'导入失败，请重试！'];
                }
            }
        }
        return $msg;
    }
}

 配置路由：

'import'=>'admin/Upload/import',  

2.前端部分：layui传文件

<a class="layui-btn layui-btn-primary import_btn" data-type="import">导入数据</a>   //点击开始上传文件操作

layui.use(['upload'],function(){
　　var upload = layui.upload;
　　upload.render({
　　　　elem:'.import_btn',
　　　　url:"{:url('admin/import')}",
　　　　accept:'file',  //普通文件
　　　　exts:'xls',     //允许的文件后缀
　　　　done:function(res){
　　　　　　//执行导入接口后操作
　　　　}
　　});
})

参考链接：https://www.cnblogs.com/52lnamp/p/9237704.html，https://blog.csdn.net/xgs736214763/article/details/78904780（感谢分享）