localhost/index.php报错 求解决

Warning: Packets out of order. Expected 0 received 1. Packet size=68 in D:\xampp\htdocs\index.php on line 8Warning: mysqli_connect(): Error while reading greeting packet. PID=15212 in D:\xampp\htdocs\index.php on line 8Warning: mysqli_connect(): (HY000/2006): MySQL server has gone away in D:\xampp\htdocs\index.php on line 8Warning: mysqli_set_charset() expects parameter 1 to be mysqli, bool given in D:\xampp\htdocs\index.php on line 9连接失败: MySQL server has gone away