php判断当前是 http还是 https

** * 判断是否SSL协议
 * @return boolean */
function is_ssl() 
{ 
if(isset($_SERVER['HTTPS']) && ('1' == $_SERVER['HTTPS'] || 'on' == strtolower($_SERVER['HTTPS']))){
 return true; 
}elseif(isset($_SERVER['SERVER_PORT']) && ('443' == $_SERVER['SERVER_PORT'] )) { return true; 
} 
return false; 
}

使用

$http = 'http://'; $http =is_ssl()?'https://':$http;