mysqli_ping
mysqli->ping()
(PHP 5)
mysqli->ping() — Pings a server connection, or tries to reconnect if the connection has gone down
說明
Procedural style:
bool mysqli_ping
( mysqli $link
)
Object oriented style (method):
mysqli
bool ping
( void
)
Checks whether the connection to the server is working. If it has gone down, and global option mysqli.reconnect is enabled an automatic reconnection is attempted.
This function can be used by clients that remain idle for a long while, to check whether the server has closed the connection and reconnect if necessary.
Return值
如果成功則回傳 TRUE，失敗則回傳 FALSE。
範例
Example#1 Object oriented style
<?php
$mysqli = new mysqli("localhost", "my_user", "my_password", "world");
/* check connection */
if (mysqli_connect_errno()) {
printf("Connect failed: %s\n", mysqli_connect_error());
exit();
}
/* check if server is alive */
if ($mysqli->ping()) {
printf ("Our connection is ok!\n");
} else {
printf ("Error: %s\n", $mysqli->error);
}
/* close connection */
$mysqli->close();
?>
Example#2 Procedural style
<?php
$link = mysqli_connect("localhost", "my_user", "my_password", "world");
/* check connection */
if (mysqli_connect_errno()) {
printf("Connect failed: %s\n", mysqli_connect_error());
exit();
}
/* check if server is alive */
if (mysqli_ping($link)) {
printf ("Our connection is ok!\n");
} else {
printf ("Error: %s\n", mysqli_error($link));
}
/* close connection */
mysqli_close($link);
?>
上例將輸出：
Our connection is ok!