Implementing WeChat Share Interface with PHP and JavaScript

When a project requires custom WeChat share titles, summaries, and images, you first need to register a WeChat public account and complete the authentication process; the account’s AppID and AppSecret are essential for the API calls.

In the WeChat public platform, navigate to Development → Basic Information to enable the developer mode and record the AppID and AppSecret. Then, under Settings → Development → JS Interface Security Domain , add the domain(s) from which your web pages will be served.

The core of the solution is a PHP class that retrieves the JS‑API ticket, generates a nonce string, builds the signature string, and returns a sign package containing appId , timestamp , nonceStr , url , and signature . The class also handles caching of access_token and jsapi_ticket in a JSON file.

class wechatClass {
    public $AppID;
    public $AppSecret;
    public $redirect_uri;
    public $DbSy;
    public $dump_url;
    public $scope;
    public function __construct() {
        parent::__construct();
        $this->AppID = "开发者密码(AppSecret)";
        $this->AppSecret = "开发者密码(AppSecret)";
    }
    public function getSignPackage() {
        $jsapiTicket = $this->getJsApiTicket();
        $protocol = (!empty($_SERVER['HTTPS']) && $_SERVER['HTTPS'] !== 'off' || $_SERVER['SERVER_PORT'] == 443) ? "https://" : "http://";
        $url = "{$protocol}{$_SERVER['HTTP_HOST']}{$_SERVER['REQUEST_URI']}";
        $timestamp = time();
        $nonceStr = $this->createNonceStr();
        $string = "jsapi_ticket={$jsapiTicket}&noncestr={$nonceStr}&timestamp={$timestamp}&url={$url}";
        $signature = sha1($string);
        $signPackage = array(
            "appId"     => $this->AppID,
            "nonceStr"  => $nonceStr,
            "timestamp" => $timestamp,
            "url"       => $url,
            "signature" => $signature,
            "rawString" => $string
        );
        return $signPackage;
    }
    public function createNonceStr($length = 16) {
        $chars = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
        $str = "";
        for ($i = 0; $i < $length; $i++) {
            $str .= substr($chars, mt_rand(0, strlen($chars) - 1), 1);
        }
        return $str;
    }
    public function getJsApiTicket() {
        $data = json_decode(file_get_contents($_SERVER['DOCUMENT_ROOT']."/static/yejuzhi/js/access_token.json"));
        if ($data->expire_time < time()) {
            $accessToken = $this->getAccessToken();
            $url = "https://api.weixin.qq.com/cgi-bin/ticket/getticket?type=jsapi&amp;access_token={$accessToken}";
            $res = json_decode($this->httpGet($url));
            $ticket = $res->ticket;
            if ($ticket) {
                $data->expire_time = time() + 7000;
                $data->jsapi_ticket = $ticket;
                $fp = fopen($_SERVER['DOCUMENT_ROOT']."/static/yejuzhi/js/access_token.json", "w");
                fwrite($fp, json_encode($data));
                fclose($fp);
            }
        } else {
            $ticket = $data->jsapi_ticket;
        }
        return $ticket;
    }
    public function getAccessToken() {
        $data = json_decode(file_get_contents($_SERVER['DOCUMENT_ROOT']."/static/yejuzhi/js/access_token.json"));
        if ($data->expire_time < time()) {
            $url = "https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&amp;appid={$this->AppID}&amp;secret={$this->AppSecret}";
            $res = json_decode($this->httpGet($url));
            $access_token = $res->access_token;
            if ($access_token) {
                $data->expire_time = time() + 7000;
                $data->access_token = $access_token;
                $fp = fopen($_SERVER['DOCUMENT_ROOT']."/static/yejuzhi/js/access_token.json", "w");
                fwrite($fp, json_encode($data));
                fclose($fp);
            }
        } else {
            $access_token = $data->access_token;
        }
        return $access_token;
    }
    public function httpGet($url) {
        $curl = curl_init();
        curl_setopt($curl, CURLOPT_RETURNTRANSFER, true);
        curl_setopt($curl, CURLOPT_TIMEOUT, 500);
        curl_setopt($curl, CURLOPT_SSL_VERIFYPEER, false);
        curl_setopt($curl, CURLOPT_SSL_VERIFYHOST, false);
        curl_setopt($curl, CURLOPT_URL, $url);
        $res = curl_exec($curl);
        curl_close($curl);
        return $res;
    }
}

In a ThinkPHP 5.1 project, instantiate the class and assign the sign package to the view:

$wx = new WeChatClass();
$sign = $wx->getSignPackage();
$this->assign('sign', $sign);

On the front end, include the WeChat JS SDK and configure wx.config with the values from the sign package, then call wx.updateAppMessageShareData (or wx.updateTimelineShareData ) to set the custom title, description, link, and image URL for sharing.

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>微信分享接口制作</title>
</head>
<body>
<script src="http://res2.wx.qq.com/open/js/jweixin-1.6.0.js"></script>
<script>
wx.config({
    debug: false,
    appId: '{$sign.appId}',
    timestamp: '{$sign.timestamp}',
    nonceStr: '{$sign.nonceStr}',
    signature: '{$sign.signature}',
    jsApiList: ["updateAppMessageShareData"]
});
wx.ready(function () {
    wx.updateAppMessageShareData({
        title: '您的标题',
        desc: '您的描述',
        link: '您的分享链接',
        imgUrl: '您的分享图标',
        success: function () {
            // 分享成功后可进行统计或提示
        }
    });
});
</script>
</body>
</html>

After deploying the PHP file and the HTML page on a server whose domain is listed in the JS security domain settings, the custom share content will appear when users share the page via WeChat.