mysqli::ping

mysqli_ping

(PHP 5)

mysqli::ping -- mysqli_ping — Pings a server connection, or tries to reconnect if the connection has gone down

说明

面向对象风格

bool mysqli::ping ( void )

过程化风格

bool mysqli_ping ( mysqli $link )

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.

参数

link: 仅以过程化样式：由 mysqli_connect() 或 mysqli_init() 返回的链接标识。

返回值

成功时返回 TRUE，或者在失败时返回 FALSE.

范例

Example #1 mysqli::ping() example

面向对象风格


<?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();
?>

过程化风格


<?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);
?>

以上例程会输出：

Our connection is ok!