(PHP 5, PHP 7)
mysqli::real_escape_string -- mysqli::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
面向对象风格
$escapestr
)过程化风格
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.
The character set must be set either at the server level, or with the API function mysqli_set_charset() for it to affect mysqli_real_escape_string(). See the concepts section on character sets for more information.
link仅以过程化样式：由mysqli_connect() 或 mysqli_init() 返回的链接标识。
escapestrThe string to be escaped.
Characters encoded are NUL (ASCII 0), \n, \r, \, ', ", and Control-Z.
Returns an escaped string.
Executing this function without a valid MySQLi connection passed in will
return NULL and emit E_WARNING level errors.
Example #1 mysqli::real_escape_string() 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();
}
$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();
?>
过程化风格
<?php
$link = mysqli_connect("localhost", "my_user", "my_password", "world");
/* check connection */
if (mysqli_connect_errno()) {
printf("Connect failed: %s\n", mysqli_connect_error());
exit();
}
mysqli_query($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);
?>
以上例程会输出：
Error: 42000 1 Row inserted.
Note:
For those accustomed to using mysql_real_escape_string(), note that the arguments of mysqli_real_escape_string() differ from what mysql_real_escape_string() expects. The
linkidentifier comes first in mysqli_real_escape_string(), whereas the string to be escaped comes first in mysql_real_escape_string().