使用php实现微信登录其实并不难，可以简单地分为三步进行。

第一步：用户同意授权，获取code

//微信登录

    public function wxlogin()
    {
        $appid = "";
        $secret = "";
        $str="http://***.***.com/getToken";
        $redirect_uri=urlencode($str);
        //通过code获得 access_token + openid
        $url="https://open.weixin.qq.com/connect/oauth2/authorize?appid=".$appid."&redirect_uri=".$redirect_uri."&response_type=code&scope=snsapi_userinfo&state=STATE#wechat_redirect";
       header("Location:" . $url);

    }

第二步：通过code换取网页授权access_token

public function getToken()

{

$code = $_GET["code"];

 

        $appid = "";

       $secret = "";

 

//通过code获得 access_token + openid

       $url="https://api.weixin.qq.com/sns/oauth2/access_token?appid=".$appid

        ."&secret=" . $secret . "&code=" . $code . "&grant_type=authorization_code";

        $jsonResult =$this->https_request($url);

        $resultArray = json_decode($jsonResult, true);

 

        $access_token = $resultArray["access_token"];

        $openid = $resultArray["openid"];

 

//第三步  获取用户信息

         //通过access_token + openid 获得用户所有信息,结果全部存储在$infoArray里,后面再写自己的代码逻辑

        $infoUrl = "https://api.weixin.qq.com/sns/userinfo?access_token=" . $access_token . "&openid=" . $openid.'&lang=zh_CN';

        $infoResult = $this->https_request($infoUrl);

        $infoArray = json_decode($infoResult, true);

 

       if($infoArray['unionid'])

        {

         

     }

 

}

附加：代码中用到的方法 

// An highlighted block

function https_request($url, $data = null)

    {

        $curl = curl_init();

        curl_setopt($curl, CURLOPT_URL, $url);

        curl_setopt($curl, CURLOPT_SSL_VERIFYPEER, FALSE);

        curl_setopt($curl, CURLOPT_SSL_VERIFYHOST, FALSE);

        if (!empty($data)){

            curl_setopt($curl, CURLOPT_POST, 1);

            curl_setopt($curl, CURLOPT_POSTFIELDS, $data);

        }

        curl_setopt($curl, CURLOPT_RETURNTRANSFER, 1);

        $output = curl_exec($curl);

        curl_close($curl);

        return $output;

    }