其實之前微信分享都是預設抓取頁面第一張圖片的，後來隨著微信的版本升級，也防止那種誘導式分享，騰訊遮蔽了這一功能，目前僅在PC版本是自動抓取，所以手機版微信分享帶縮圖及簡介的話就要使用jssdk。我之前也是不會，後來網上看到了一大神寫的，參照他的，自己寫了一下這個功能。這個是基於ecshop寫的

商品詳情頁程式碼：

<script type="text/javascript" src="http://res.wx.qq.com/open/js/jweixin-1.2.0.js"></script>
<script type="text/javascript">

    wx.config({
        debug: false
 
, // 開啟除錯模式,呼叫的所有api的返回值會在客戶端alert出來，若要檢視傳入的引數，可以在pc端開啟，引數資訊會通過log打出，僅在pc端時才會列印。
        appId: "{$signPackage.appId}", // 必填，公眾號的唯一標識
        timestamp: "{$signPackage.timestamp}", // 必填，生成簽名的時間戳
        nonceStr: "{$signPackage.nonceStr}", // 必填，生成簽名的隨機串
        signature: "{$signPackage.signature}",// 必填，簽名，見附錄1
 

        jsApiList: ['onMenuShareTimeline', 'onMenuShareAppMessage'] // 必填，需要使用的JS介面列表，所有JS介面列表見附錄2
    });

    wx.ready(function(){

       //IOS系統分享時讀取圖片路徑會出現問題 用 encodeURI 來處理下
        var img_url = encodeURI("http://{$smarty.server.SERVER_NAME}{$goods_share_img}");

         //分享到朋友圈
        wx.onMenuShareTimeline({
            title: "{$goods.goods_style_name}"
 
, // 分享標題
            link: "http://{$smarty.server.SERVER_NAME}{$smarty.server.REQUEST_URI}", // 分享連結，該連結域名或路徑必須與當前頁面對應的公眾號JS安全域名一致
            imgUrl: img_url, // 分享圖示

            success: function () { 
                alert('已分享');
            },
            cancel: function () { 
                alert('已取消');
            }
        });

       //分享給微信好友
        wx.onMenuShareAppMessage({
            title: "{$goods.goods_style_name}", // 分享標題
            desc: "{$goods.goods_style_name}", // 分享描述
            link: "http://{$smarty.server.SERVER_NAME}{$smarty.server.REQUEST_URI}", // 分享連結，該連結域名或路徑必須與當前頁面對應的公眾號JS安全域名一致
            imgUrl: img_url, // 分享圖示
            type: '', // 分享型別,music、video或link，不填預設為link
            dataUrl: '', // 如果type是music或video，則要提供資料鏈接，預設為空

            success: function () { 
                 alert('已分享');
            },
            cancel: function () { 
                alert('已取消');
            }
        });
    });
</script>

PHP指令碼程式碼：

// 微信分享 start
//把要用全部封裝一個方法裡，方便模版中使用
function getSignPackage() {
    $jsapiTicket = 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 = createNonceStr();
    $string = "jsapi_ticket=$jsapiTicket&noncestr=$nonceStr&timestamp=$timestamp&url=$url";
    $signature = sha1($string);//生成簽名
    $signPackage = array(
      "appId"     => 'wxf888b6qb96c0cf91', //自己公眾號的AppId,我這裡隨便寫一個
      "nonceStr"  => $nonceStr,
      "timestamp" => $timestamp,
      "signature" => $signature
    );
    return $signPackage; 
}
//生成隨機字串
function createNonceStr($length = 16) {
    $chars = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
    $str = "";
    for ($i = 0; $i < $length; $i++) {
      $str .= substr($chars, mt_rand(0, strlen($chars) - 1), 1);
    }
    return $str;
}
//獲取jsapi_ticket
function getJsApiTicket() {
    $data = $_SESSION['jsapiticket_all'];
    if ($data['expire_time'] < time()) {
      $accessToken = getAccessToken();
      $url = "https://api.weixin.qq.com/cgi-bin/ticket/getticket?type=jsapi&access_token=$accessToken";
      $res = json_decode(httpGet($url));
      foreach ($res as $k=>$v){
           $all[$k] = $v;
      }
      $ticket = $all['ticket'];
      if ($ticket) {
       $_SESSION['jsapiticket_all']['expire_time'] = time() + 7000;
       $_SESSION['jsapiticket_all']['jsapi_ticket'] = $ticket;
      }
    } else {
      $ticket = $_SESSION['jsapiticket_all']['jsapi_ticket'];
    }

    return $ticket;
}
//獲取AccessToken
function getAccessToken() {
    $data = $_SESSION['access_token_all'];
    if ($data['expire_time'] < time()) {
      $url = "https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid=wxb338b6a276c0cf25&secret=28cafa17194e9241e6685260b7ebef89";
      $res = json_decode(httpGet($url));
      foreach ($res as $k=>$v){
           $all[$k] = $v;
      }
      $access_token = $all['access_token'];
      if ($access_token) {
            $_SESSION['access_token_all']['expire_time'] = time() + 7000;
            $access_token = $all['access_token'];
            $_SESSION['access_token_all'] =$all;
      }
    } else {
      $access_token = $_SESSION['access_token_all']['access_token'];
    }
    return $access_token;
}
//安全處理
function httpGet($url) {
    $curl = curl_init();
    curl_setopt($curl, CURLOPT_RETURNTRANSFER, true);
    curl_setopt($curl, CURLOPT_TIMEOUT, 500);
    curl_setopt($curl, CURLOPT_SSL_VERIFYPEER, true);
    curl_setopt($curl, CURLOPT_SSL_VERIFYHOST, true);
    curl_setopt($curl, CURLOPT_URL, $url);

    $res = curl_exec($curl);
    curl_close($curl);

    return $res;
}

$smarty->assign('signPackage',getSignPackage()); //賦值到模板
// 微信分享end