如何在微信支付V3PHP版请求中添加header?

刚看了微信支付v3服务商php版文档,要求必须在请求中添加header,但是没有看懂如何在请求中添加header??
示例如下:

$resp = $instance
    ->chain('v3/pay/transactions/native')
    ->post(['json' => [
        'mchid'        => '1900006XXX',
        'out_trade_no' => 'native12177525012014070332333',
        'appid'        => 'wxdace645e0bc2cXXX',
        'description'  => 'Image形象店-深圳腾大-QQ公仔',
        'notify_url'   => 'https://weixin.qq.com/',
        'amount'       => [
            'total'    => 1,
            'currency' => 'CNY'
        ],
    ]]);

如何添加header呢,是直接添加到post中吗,请懂给说下。

你看下这个实例【关于微信支付小程序v3【附PHP完整后端代码】】,不知是否符合你的需求,链接:https://jiuaidu.com/jianzhan/919029/

header('Content-type:text/html; Charset=utf-8');
ini_set('date.timezone','Asia/Shanghai');
$data_s = file_get_contents('php://input');
$data_s = json_decode($data_s,true);
if(empty($data_s['out_trade_no'])){
    exit;
}

希望对你有所帮助
https://blog.csdn.net/weixin_39908588/article/details/115169526?ops_request_misc=&request_id=&biz_id=102&utm_term=808%E5%A6%82%E4%BD%95%E5%9C%A8%E5%BE%AE%E4%BF%A1%E6%94%AF%E4%BB%98V3PHP%E7%89%88%E8%AF%B7%E6%B1%82%E4%B8%AD%E6%B7%BB%E5%8A%A0header%EF%BC%9F6C&utm_medium=distribute.pc_search_result.none-task-blog-2~all~sobaiduweb~default-2-115169526.142^v67^pc_rank_34_queryrelevant25,201^v3^add_ask,213^v2^t3_esquery_v1&spm=1018.2226.3001.4449