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## Sanitize filters

List of filters for sanitization
ID | Name | Flags | Description
--- | --- | --- | ---
`FILTER_SANITIZE_EMAIL` | "email" |  | Remove all characters except letters, digits and !#$%&'*+-/=?^_`{|}~@.[].
`FILTER_SANITIZE_ENCODED` | "encoded" | `FILTER_FLAG_STRIP_LOW`, `FILTER_FLAG_STRIP_HIGH`, `FILTER_FLAG_ENCODE_LOW`, `FILTER_FLAG_ENCODE_HIGH` | URL-encode string, optionally strip or encode special characters.
`FILTER_SANITIZE_MAGIC_QUOTES` | "magic_quotes" |  | Apply addslashes().
`FILTER_SANITIZE_NUMBER_FLOAT` | "number_float" | `FILTER_FLAG_ALLOW_FRACTION`, `FILTER_FLAG_ALLOW_THOUSAND`, `FILTER_FLAG_ALLOW_SCIENTIFIC` | Remove all characters except digits, +- and optionally .,eE.
`FILTER_SANITIZE_NUMBER_INT` | "number_int" |  | Remove all characters except digits, plus and minus sign.
`FILTER_SANITIZE_SPECIAL_CHARS` | "special_chars" | `FILTER_FLAG_STRIP_LOW`, `FILTER_FLAG_STRIP_HIGH`, `FILTER_FLAG_ENCODE_HIGH` | HTML-escape '"<>& and characters with ASCII value less than 32, optionally strip or encode other special characters.
`FILTER_SANITIZE_FULL_SPECIAL_CHARS` | "full_special_chars" | `FILTER_FLAG_NO_ENCODE_QUOTES`, | Equivalent to calling htmlspecialchars() with `ENT_QUOTES` set. Encoding quotes can be disabled by setting `FILTER_FLAG_NO_ENCODE_QUOTES`. Like htmlspecialchars(), this filter is aware of the default_charset and if a sequence of bytes is detected that makes up an invalid character in the current character set then the entire string is rejected resulting in a 0-length string. When using this filter as a default filter, see the warning below about setting the default flags to 0.
`FILTER_SANITIZE_STRING` | "string" | `FILTER_FLAG_NO_ENCODE_QUOTES`, `FILTER_FLAG_STRIP_LOW`, `FILTER_FLAG_STRIP_HIGH`, `FILTER_FLAG_ENCODE_LOW`, `FILTER_FLAG_ENCODE_HIGH`, `FILTER_FLAG_ENCODE_AMP` | Strip tags, optionally strip or encode special characters.
`FILTER_SANITIZE_STRIPPED` | "stripped" |  | Alias of "string" filter.
`FILTER_SANITIZE_URL` | "url" |  | Remove all characters except letters, digits and $-_.+!*'(),{}|\\^~[]`<>#%";/?:@&=.
`FILTER_UNSAFE_RAW` | "unsafe_raw" | `FILTER_FLAG_STRIP_LOW`, `FILTER_FLAG_STRIP_HIGH`, `FILTER_FLAG_ENCODE_LOW`, `FILTER_FLAG_ENCODE_HIGH`, `FILTER_FLAG_ENCODE_AMP` | Do nothing, optionally strip or encode special characters. This filter is also aliased to `FILTER_DEFAULT`.

Warning

When using one of these filters as a default filter either through your ini file or through your web server's configuration, the default flags is set to `FILTER_FLAG_NO_ENCODE_QUOTES`. You need to explicitly set filter.default_flags to 0 to have quotes encoded by default. Like this:

Example #1 Configuring the default filter to act like htmlspecialchars

`filter.default = full_special_chars
filter.default_flags = 0`

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