mysqli::real_connect
You can avoid all character escaping issues (on the PHP side) if you use prepare() and bind_param(), as an alternative to placing arbitrary string values in SQL statements. This works because bound parameter values are NOT passed via the SQL statement syntax.
mysqli::real_escape_string
mysqli_real_escape_string
(PHP 5)
mysqli::real_escape_string -- mysqli_real_escape_string — Escapes special characters in a string for use in an SQL statement, taking into account the current charset of the connection
Descripción
Estilo orientado a objetos
string mysqli::real_escape_string
( string $escapestr
)
Estilo por procesos
This function is used to create a legal SQL string that you can use in an SQL statement. The given string is encoded to an escaped SQL string, taking into account the current character set of the connection.
Parámetros
- link
-
Sólo estilo procedimental: Un identificador de enlace devuelto por mysqli_connect() o mysqli_init()
- escapestr
-
The string to be escaped.
Characters encoded are NUL (ASCII 0), \n, \r, \, ', ", and Control-Z.
Valores devueltos
Returns an escaped string.
Ejemplos
Example #1 mysqli::real_escape_string() example
Estilo orientado a objetos
<?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();
}
$mysqli->query("CREATE TEMPORARY TABLE myCity LIKE City");
$city = "'s Hertogenbosch";
/* this query will fail, cause we didn't escape $city */
if (!$mysqli->query("INSERT into myCity (Name) VALUES ('$city')")) {
printf("Error: %s\n", $mysqli->sqlstate);
}
$city = $mysqli->real_escape_string($city);
/* this query with escaped $city will work */
if ($mysqli->query("INSERT into myCity (Name) VALUES ('$city')")) {
printf("%d Row inserted.\n", $mysqli->affected_rows);
}
$mysqli->close();
?>
Estilo por procesos
<?php
$link = mysqli_connect("localhost", "my_user", "my_password", "world");
/* check connection */
if (mysqli_connect_errno()) {
printf("Connect failed: %s\n", mysqli_connect_error());
exit();
}
mysqli_query($link, "CREATE TEMPORARY TABLE myCity LIKE City");
$city = "'s Hertogenbosch";
/* this query will fail, cause we didn't escape $city */
if (!mysqli_query($link, "INSERT into myCity (Name) VALUES ('$city')")) {
printf("Error: %s\n", mysqli_sqlstate($link));
}
$city = mysqli_real_escape_string($link, $city);
/* this query with escaped $city will work */
if (mysqli_query($link, "INSERT into myCity (Name) VALUES ('$city')")) {
printf("%d Row inserted.\n", mysqli_affected_rows($link));
}
mysqli_close($link);
?>
El resultado de los ejemplos serían:
Error: 42000 1 Row inserted.
Ver también
- mysqli_character_set_name() - Devuelve el juego de caracteres predeterminado para la conexión a base de datos
add a note
User Contributed Notes
mysqli::real_escape_string
dave at mausner.us
25-Feb-2011 03:48
Josef Toman
26-Feb-2010 02:14
For percent sign and underscore I use this:
<?php
$more_escaped = addcslashes($escaped, '%_');
?>
vita dot plachy at seznam dot cz
09-Nov-2007 07:37
The above can be managed by the following function:
<?php
function search_escape($str, $char = '\\')
{
return ereg_replace('[%_]', $char . '\0', $str);
}
?>
tobias_demuth at web dot de
10-Nov-2005 04:54
Note, that if no connection is open, mysqli_real_escape_string() will return an empty string!
arnoud at procurios dot nl
07-Oct-2004 04:05
Note that this function will NOT escape _ (underscore) and % (percent) signs, which have special meanings in LIKE clauses.
As far as I know there is no function to do this, so you have to escape them yourself by adding a backslash in front of them.