How to use php addcslashes function?

php The addcslashes function is used to add a backslash string before the specified character. Its syntax is addcslashes(string,characters). The parameter string is required and specifies the string to be escaped; characters is required and specifies the string to be escaped. Character or range of characters.

php How to use addcslashes function?

Definition and usage

addcslashes() function returns a string with a backslash added before the specified character.

Note: The addcslashes() function is case-sensitive.

Note: Please be careful when applying addcslashes() to the following characters: 0 (NULL), r (carriage return), n (line feed), f (form feed), t (tab), and v (vertical Tabs). In PHP, \0, \r, \n, \t, \f and \v are predefined escape sequences.

Syntax

addcslashes(string,characters)

Parameters

string Required. Specifies the string to be escaped.

characters Required. Specifies the characters or range of characters to be escaped.

Return value: Returns the escaped string.

PHP Version: 4

Example 1

Add backslash to specific characters in a string:

<?php
$str = "Welcome to Shanghai!";
echo $str."<br>";
echo addcslashes($str,&#39;m&#39;)."<br>";
echo addcslashes($str,&#39;H&#39;)."<br>";
?>

Output :

Welcome to Shanghai!
Welcome to Sh\angh\ai!
Welcome to \Shanghai!

Example 2

Add backslash to a range of characters in a string:

<?php
$str = "Welcome to Shanghai!";
echo $str."<br>";
echo addcslashes($str,&#39;A..Z&#39;)."<br>";
echo addcslashes($str,&#39;a..z&#39;)."<br>";
echo addcslashes($str,&#39;a..g&#39;);
?>

Output:

Welcome to Shanghai!
\Welcome to \Shanghai!
W\e\l\c\o\m\e \t\o S\h\a\n\g\h\a\i!
W\el\com\e to Sh\an\gh\ai!

Example 3

Add a backslash before the character "A":

<?php
$str = addcslashes("A001 A002 A003","A");
echo($str);
?>

Output:

\A001 \A002 \A003

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