addcslashes
Quote string with slashes in a C style
Description
string addcslashes(string $string, string $characters)
Parameters
-
string
-
The string to be escaped.
-
characters
-
A list of characters to be escaped. If
characters contains characters
\n, \r etc., they are
converted in C-like style, while other non-alphanumeric characters
with ASCII codes lower than 32 and higher than 126 converted to
octal representation.
When you define a sequence of characters in the characters argument
make sure that you know what characters come between the
characters that you set as the start and end of the range.
Example #1 addcslashes with Ranges
<?php
echo addcslashes('foo[ ]', 'A..z');
// output: \f\o\o\[ \]
// All upper and lower-case letters will be escaped
// ... but so will the [\]^_`
?>
Also, if the first character in a range has a higher ASCII value
than the second character in the range, no range will be
constructed. Only the start, end and period characters will be
escaped. Use the ord function to find the
ASCII value for a character.
Example #2 addcslashes with Characters in Wrong Order
<?php
echo addcslashes("zoo['.']", 'z..A');
// output: \zoo['\.']
?>
Be careful if you choose to escape characters 0, a, b, f, n, r, t and
v. They will be converted to \0, \a, \b, \f, \n, \r, \t and \v, all of
which are predefined escape sequences in C. Many of these sequences are
also defined in other C-derived languages, including PHP, meaning that
you may not get the desired result if you use the output of
addcslashes to generate code in those languages
with these characters defined in characters.
Return Values
Returns the escaped string.
Examples
characters like "\0..\37", which would
escape all characters with ASCII code between 0 and 31.
Example #3 addcslashes example
<?php
$not_escaped = "PHP isThirty\nYears Old!\tYay to the Elephant!\n";
$escaped = addcslashes($not_escaped, "\0..\37!@\177..\377");
echo $escaped;
?>
See Also
- stripcslashes
- stripslashes
- addslashes
- htmlspecialchars
- quotemeta