PHP backslash function addslashes () and stripslashes () tutorial

PHP Backslash handler function

Addslashes (): Adds a backslash to some predefined characters in the input string so that the processing is required for database query statements, and so on. These predefined characters are: Single quotes ('), double quotes ("), backslash (\), NULL.

Stripslashes (): Deletes the backslash that was added by the addslashes () function. This function is used to clean up data retrieved from a database or HTML form. (if two consecutive backslash, then remove one, keep one, if only a backslash, directly removed.) )

By default, the PHP directive MAGIC_QUOTES_GPC to on and automatically runs Addslashes () for all get, POST, and COOKIE data. Do not use Addslashes () on strings that have been escaped by MAGIC_QUOTES_GPC, because this can result in a double escape. You can use the function GET_MAGIC_QUOTES_GPC () for instrumentation when this situation is encountered. Cases:

if (GET_MAGIC_QUOTES_GPC ()) { Code ..... }

Addslashes () Example:

<?php $str = "Who ' s John Adams?"; Echo$str. " This isn't safe in a database query.<br/> "; Echoaddslashes ($STR). " This is safe in a database query. ?>

Output results:

Who ' s John Adams? This isn't safe in a database query. Who\ ' s John Adams? This is safe in a database query.

Stripslashes () Example:

<?php Echostripslashes ("who\ ' s John Adams)"; ?>

Output results:

Who ' s John Adams?

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