<?php
/**
 * Created by PhpStorm.
 * User: JZ
 * Date: 2019/7/19
 * Time: 9:34
 */

class Attachment implements JsonSerializable {
    private $id;
    private $title;
    private $required;
    private $needSign;

    public function jsonSerialize() {
        $data = [];
        foreach ($this as $key=>$val){
            if ($val !== null) $data[$key] = $val;
        }
        if(sizeof($data) < 1){
            return null;
        }
        return $data;
    }

    /**
     * @return mixed
     */
    public function getId()
    {
        return $this->id;
    }

    /**
     * @param mixed $id
     */
    public function setId($id)
    {
        $this->id = $id;
    }

    /**
     * @return mixed
     */
    public function getTitle()
    {
        return $this->title;
    }

    /**
     * @param mixed $title
     */
    public function setTitle($title)
    {
        $this->title = $title;
    }

    /**
     * @return mixed
     */
    public function getRequired()
    {
        return $this->required;
    }

    /**
     * @param mixed $required
     */
    public function setRequired($required)
    {
        $this->required = $required;
    }

    /**
     * @return mixed
     */
    public function getNeedSign()
    {
        return $this->needSign;
    }

    /**
     * @param mixed $needSign
     */
    public function setNeedSign($needSign)
    {
        $this->needSign = $needSign;
    }

}