PHP md5(IP+操作系统类型+浏览器类型+浏览器版本号) 联合唯一

   $ip = request()->ip();
   //今天
   $timetoday = strtotime(date("Y-m-d", time()));
		
   //md5(IP+操作系统类型+浏览器类型+浏览器版本号) 联合唯一
   $ip = md5($ip.$this->get_client_browser().$this->get_client_os()); 

   /**
     * 获取客户端浏览器
     */
    public function get_client_browser()
    {
    	$sys = $_SERVER['HTTP_USER_AGENT'];  //获取用户代理字符串  
	    if (stripos($sys, "Firefox/") > 0) {
	        preg_match("/Firefox\/([^;)]+)+/i", $sys, $b);  
	        $exp[0] = "Firefox";
	        $exp[1] = $b[1];  //获取火狐浏览器的版本号  
	    } elseif (stripos($sys, "Maxthon") > 0) {
	        preg_match("/Maxthon\/([\d\.]+)/", $sys, $aoyou);  
	        $exp[0] = "傲游";
	        $exp[1] = $aoyou[1];
	    } elseif (stripos($sys, "MSIE") > 0) {
	        preg_match("/MSIE\s+([^;)]+)+/i", $sys, $ie);  
	        $exp[0] = "IE";
	        $exp[1] = $ie[1];  //获取IE的版本号  
	    } elseif (stripos($sys, "OPR") > 0) {
	        preg_match("/OPR\/([\d\.]+)/", $sys, $opera);  
	        $exp[0] = "Opera";
	        $exp[1] = $opera[1];
	    } elseif(stripos($sys, "Edge") > 0) {
	        //win10 Edge浏览器 添加了chrome内核标记 在判断Chrome之前匹配  
	        preg_match("/Edge\/([\d\.]+)/", $sys, $Edge);  
	        $exp[0] = "Edge";
	        $exp[1] = $Edge[1];
	    } elseif (stripos($sys, "Chrome") > 0) {
	        preg_match("/Chrome\/([\d\.]+)/", $sys, $google);  
	        $exp[0] = "Chrome";
	        $exp[1] = $google[1];  //获取google chrome的版本号  
	    } elseif(stripos($sys,'rv:')>0 && stripos($sys,'Gecko')>0){
	        preg_match("/rv:([\d\.]+)/", $sys, $IE);
	        $exp[0] = "IE";
	        $exp[1] = $IE[1];
	    }else {
	        $exp[0] = "未知浏览器";
	        $exp[1] = ""; 
	    }
	    return $exp[0].$exp[1];  
    }
    
	/**
     * 获取客户端操作系统
     */
	public function get_client_os()
	{
	  	$agent = $_SERVER['HTTP_USER_AGENT'];  
	    $os = false;  
	    if (preg_match('/win/i', $agent) && strpos($agent, '95')){  
	        $os = 'Windows 95';  
	    }else if (preg_match('/win 9x/i', $agent) && strpos($agent, '4.90')){  
	        $os = 'Windows ME';  
	    }else if (preg_match('/win/i', $agent) && preg_match('/98/i', $agent)){  
	        $os = 'Windows 98';  
	    }else if (preg_match('/win/i', $agent) && preg_match('/nt 6.0/i', $agent)){  
	        $os = 'Windows Vista';  
	    }else if (preg_match('/win/i', $agent) && preg_match('/nt 6.1/i', $agent)){  
	        $os = 'Windows 7';  
	    }else if (preg_match('/win/i', $agent) && preg_match('/nt 6.2/i', $agent)){  
	        $os = 'Windows 8';  
	    }else if(preg_match('/win/i', $agent) && preg_match('/nt 10.0/i', $agent)){  
	        $os = 'Windows 10';#添加win10判断  
	    }else if (preg_match('/win/i', $agent) && preg_match('/nt 5.1/i', $agent)){  
	        $os = 'Windows XP';  
	    }else if (preg_match('/win/i', $agent) && preg_match('/nt 5/i', $agent)){  
	        $os = 'Windows 2000';  
	    }else if (preg_match('/win/i', $agent) && preg_match('/nt/i', $agent)){  
	        $os = 'Windows NT';  
	    }else if (preg_match('/win/i', $agent) && preg_match('/32/i', $agent)){  
	        $os = 'Windows 32';  
	    }else if (preg_match('/linux/i', $agent)){  
	        $os = 'Linux';  
	    }else if (preg_match('/unix/i', $agent)){  
	        $os = 'Unix';  
	    }else if (preg_match('/sun/i', $agent) && preg_match('/os/i', $agent)){  
	        $os = 'SunOS';  
	    }else if (preg_match('/ibm/i', $agent) && preg_match('/os/i', $agent)){  
	        $os = 'IBM OS/2';  
	    }else if (preg_match('/Mac/i', $agent) && preg_match('/PC/i', $agent)){  
	        $os = 'Macintosh';  
	    }else if (preg_match('/PowerPC/i', $agent)){  
	        $os = 'PowerPC';  
	    }else if (preg_match('/AIX/i', $agent)){  
	        $os = 'AIX';  
	    }else if (preg_match('/HPUX/i', $agent)){  
	        $os = 'HPUX';  
	    }else if (preg_match('/NetBSD/i', $agent)){  
	        $os = 'NetBSD';  
	    }else if (preg_match('/BSD/i', $agent)){  
	        $os = 'BSD';  
	    }else if (preg_match('/OSF1/i', $agent)){  
	        $os = 'OSF1';  
	    }else if (preg_match('/IRIX/i', $agent)){  
	        $os = 'IRIX';  
	    }else if (preg_match('/FreeBSD/i', $agent)){  
	        $os = 'FreeBSD';  
	    }else if (preg_match('/teleport/i', $agent)){  
	        $os = 'teleport';  
	    }else if (preg_match('/flashget/i', $agent)){  
	        $os = 'flashget';  
	    }else if (preg_match('/webzip/i', $agent)){  
	        $os = 'webzip';  
	    }else if (preg_match('/offline/i', $agent)){  
	        $os = 'offline';  
	    }else{  
	        $os = '未知操作系统';  
	    }
	    return $os;
	}