<form action="{:U('Config/addImg')}" enctype="multipart/form-data" method="post" >

    <input type="text" name="name" /><br>

    <input type="file" name="photo[]" /><br>

    <input type="submit" value="提交" >

</form>

public function addImg(){

    $upload = new \Think\Upload();// 实例化上传类

    $upload->maxSize   =     3145728 ;// 设置附件上传大小

    $upload->exts      =     array('jpg', 'gif', 'png', 'jpeg');// 设置附件上传类型

    $upload->rootPath  =     "./Application/uploads/"; // 设置附件上传根目录

    $upload->savePath  =     ''; // 设置附件上传（子）目录

    // 上传文件

    $info   =   $upload->upload();

    if(!$info){

        json_encode("上传失败");die;

    };

    $path = "Application/uploads/".$info['file']['savepath'].$info['file']['savename'];

    echo $path;

}