API程式碼：

//-------配置
$AppID = C('WX_APPID');
$AppSecret = C('WX_APPSECRET');
$callback  = C('WX_CALLBACK');//'http://www.wftc.co//'; //回撥地址
//微信登入
session_start();
//-------生成唯一隨機串防CSRF攻擊
$state  = md5(uniqid(rand(), TRUE));
$_SESSION["wx_state"]    =   $state; //存到SESSION
$callback = urlencode($callback);
$wxurl = "https://open.weixin.qq.com/connect/qrconnect?appid=".$AppID."&redirect_uri={$callback}&response_type=code&scope=snsapi_login&state={$state}#wechat_redirect";
header("Location: $wxurl");
 

if($_GET['state']!=$_SESSION["wx_state"]){
      exit("5001");
}

$AppID = C('WX_APPID');
$AppSecret = C('WX_APPSECRET');
$url='https://api.weixin.qq.com/sns/oauth2/access_token?appid='.$AppID.'&secret='.$AppSecret.'&code='.$_GET['code'].'&grant_type=authorization_code';

$ch = curl_init();
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, FALSE);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, TRUE);
curl_setopt($ch, CURLOPT_URL, $url);
$json =  curl_exec($ch);
curl_close($ch);

$arr=json_decode($json,1);

//得到 access_token 與 openid
 //print_r($arr); 

// exit;

$url='https://api.weixin.qq.com/sns/userinfo?access_token='.$arr['access_token'].'&openid='.$arr['openid'].'&lang=zh_CN';
//exit($url);
$ch = curl_init();
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, FALSE);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, TRUE);
curl_setopt($ch, CURLOPT_URL, $url);
$json =  curl_exec($ch);
curl_close($ch);
$arr=json_decode($json,1);
//得到 使用者資料
print_r($arr);