1：在微信公众号后台配置js 安全域名，即需要引入jssdk的页面域名。 需要在域名根目录下放置微信的检测文件。

2：配置出ip白名单（可参考:http://www.idcxx.com/wx-125-1-1.html）

3：后台开发人员生成签名传递给前台

4：前端页面引入script方式 jssdk文件

5：通过ajax获取config 配置，完成config 配置后即可使用jssdk的各项功能了。

<script src="http://外部站点引入/js/jquery-1.11.1.min.js"></script>  

<script src="http://res.wx.qq.com/open/js/jweixin-1.0.0.js"></script>
<script>
var url=encodeURIComponent(window.location.href.split('#')[0]);//分享成功之后再次分享，微信会再url附带额外参数造成二次分享签名错误，这里处理下避免config：invalid signature签名失效$.ajax({type : "get",url : "http://xxx/jssdk.php?url="+url,//替换网址，xxx根据自己jssdk文件位置修改
    dataType : "jsonp",jsonp: "callback",jsonpCallback:"success_jsonpCallback",success : function(data){wx.config({　　　　 debug: true, // 开启调试模式,调用的所有api的返回值会在客户端alert出来，若要查看传入的参数，可以在pc端打开，参数信息会通过log打出，仅在pc端时才会打印appId: data.appId,timestamp: data.timestamp,nonceStr: data.nonceStr,signature: data.signature,jsApiList: ["onMenuShareTimeline", //分享给好友"onMenuShareAppMessage", //分享到朋友圈"onMenuShareQQ",  //分享到QQ"onMenuShareWeibo" //分享到微博
]
});
},error:function(data){　　　　　　alert(JSON.stringify(data));//alert("连接失败！");}
});wx.ready(function (){var shareData = {title: '标题',desc: '简介',//这里请特别注意是要去除html
  link: '链接',imgUrl: '标题图'};wx.onMenuShareAppMessage(shareData);wx.onMenuShareTimeline(shareData);wx.onMenuShareQQ(shareData);wx.onMenuShareWeibo(shareData);});
</script>

<?php
$url = urldecode($_GET['url']);
class JSSDK {private $appId;private $appSecret;private $url;public function __construct($appId, $appSecret,$url) {$this->appId = $appId;$this->appSecret = $appSecret;$this->url = $url;}public function getSignPackage() {$jsapiTicket = $this->getJsApiTicket();$protocol = (!empty($_SERVER['HTTPS']) && $_SERVER['HTTPS'] !== 'off' || $_SERVER['SERVER_PORT'] == 443) ? "https://" : "http://";// $url = "$protocol$_SERVER[HTTP_HOST]$_SERVER[REQUEST_URI]";$url =$this->url;$timestamp = time();$nonceStr = $this->createNonceStr();// 这里参数的顺序要按照 key 值 ASCII 码升序排序$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 $signPackage; }private function createNonceStr($length = 16) {$chars = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";$str = "";for ($i = 0; $i < $length; $i++) {$str .= substr($chars, mt_rand(0, strlen($chars) - 1), 1);}return $str;}private function getJsApiTicket() {// jsapi_ticket 应该全局存储与更新，以下代码以写入到文件中做示例$data = json_decode(file_get_contents("jsapi_ticket.json"));if ($data->expire_time < time()) {$accessToken = $this->getAccessToken();// 如果是企业号用以下 URL 获取 ticket// $url = "https://qyapi.weixin.qq.com/cgi-bin/get_jsapi_ticket?access_token=$accessToken";$url = "https://api.weixin.qq.com/cgi-bin/ticket/getticket?type=jsapi&access_token=$accessToken";$res = json_decode($this->httpGet($url));$ticket = $res->ticket;if ($ticket) {$data->expire_time = time() + 7000;$data->jsapi_ticket = $ticket;$fp = fopen("jsapi_ticket.json", "w");fwrite($fp, json_encode($data));fclose($fp);}} else {$ticket = $data->jsapi_ticket;}return $ticket;}private function getAccessToken() {// access_token 应该全局存储与更新，以下代码以写入到文件中做示例$data = json_decode(file_get_contents("access_token.json"));if ($data->expire_time < time()) {// 如果是企业号用以下URL获取access_token// $url = "https://qyapi.weixin.qq.com/cgi-bin/gettoken?corpid=$this->appId&corpsecret=$this->appSecret";$url = "https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid=$this->appId&secret=$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("access_token.json", "w");fwrite($fp, json_encode($data));fclose($fp);}} else {$access_token = $data->access_token;}return $access_token;}private function httpGet($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 $res;}
}$jssdk = new JSSDK("公众号ID", "公众号密钥",$url);//按照自己的公众号填写
$signPackage = $jssdk->GetSignPackage();
$tmp=json_encode(array ('appId'=>$signPackage["appId"],'timestamp'=>$signPackage["timestamp"],'nonceStr'=>$signPackage["nonceStr"],'signature'=>$signPackage["signature"],'url'=>$signPackage["url"]));
$callback = $_GET['callback'];
echo $callback.'('.$tmp.')';
exit;
?>