mysqli_connect
mysqli->__construct()
(No version information available, might be only in CVS)
mysqli->__construct() — Open a new connection to the MySQL server
说明
Procedural style
mysqli mysqli_connect
([ string $host
[, string $username
[, string $passwd
[, string $dbname
[, int $port
[, string $socket
]]]]]] )
Object oriented style (constructor):
mysqli
__construct
([ string $host
[, string $username
[, string $passwd
[, string $dbname
[, int $port
[, string $socket
]]]]]] )
Opens a connection to the MySQL Server running on.
参数
-
host
-
Can be either a host name or an IP address. Passing the NULL value
or the string "localhost" to this parameter, the local host is
assumed. When possible, pipes will be used instead of the TCP/IP
protocol.
-
username
-
The MySQL user name.
-
passwd
-
If not provided or NULL, the MySQL server will attempt to authenticate
the user against those user records which have no password only. This
allows one username to be used with different permissions (depending
on if a password as provided or not).
-
dbname
-
If provided will specify the default database to be used when
performing queries.
-
port
-
Specifies the port number to attempt to connect to the MySQL server.
-
socket
-
Specifies the socket or named pipe that should be used.
Note:
Specifying the socket
parameter will not
explicitly determine the type of connection to be used when
connecting to the MySQL server. How the connection is made to the
MySQL database is determined by the host
parameter.
返回值
Returns a object which represents the connection to a MySQL Server or
FALSE if the connection failed.
范例
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();
}
printf("Host information: %s\n", $mysqli->host_info);
/* close connection */
$mysqli->close();
?>
Example#2 Procedural style
<?php
$link = mysqli_connect("localhost", "my_user", "my_password", "world");
/* check connection */
if (!$link) {
printf("Connect failed: %s\n", mysqli_connect_error());
exit();
}
printf("Host information: %s\n", mysqli_get_host_info($link));
/* close connection */
mysqli_close($link);
?>
上例将输出：
Host information: Localhost via UNIX socket
注释
Note:
Error "Can't create TCP/IP socket (10106)" usually means that the variables_order configure directive
doesn't contain character E. On Windows, if the
environment is not copied the SYSTEMROOT environment
variable won't be available and PHP will have problems loading Winsock.