PHP character escape function reference

if(phpversion() < '5.3.0') {
set_magic_quotes_runtime(0);
}

>> Magic_quotes_gpc cannot be defined through a function, so it is recommended to unify it on the server Turn it on. You should make a judgment when writing a program to avoid security issues caused by not turning on gpc. When escaping gpc through addslashes, attention should be paid to the filtering of key and value when users submit array data.

if(!get_magic_quotes_gpc()) {
$_get = daddslashes($_get);
$_post = daddslashes($_post);
$_cookie = daddslashes($_cookie);
 $_files = daddslashes($_files);
}
function daddslashes($string, $force = 1) {
if(is_array($string)) {
foreach($string as $key => $val) {
 unset($string[$key]);
$string[addslashes($key)] = daddslashes($val, $force);
}
} else {
$string = addslashes($string);
}
return $string;
}
?>>

Use to escape html entities when user input or output to prevent xss vulnerabilities produce!

Today I encountered a problem with processing special characters in files. I noticed this problem again. In php:

$str = "ffff
-----------------------
9 
        102 102 102 102 0 102 102 102 102

Example of replacing special characters

Octal ascii code example:

$str = "
-----------------------
11
        0 1 2 3 7 8 9 0 56 92 56

Hexadecimal ascii code example:





$str = "x0x1x2x3x7x8x9x10x11xff";
echo(strlen($str));

Copy code

Example of php regular expression escape characters

Commonly used escape character functions in PHP

PHP function to escape regular expression characters

php code to implement anti-injection and form submission value escaping