Regular expressions: Difference between revisions

Revision as of 12:48, 11 June 2013

Regular expressions can be used in the advanced profile fields/custom profile fields.

The input mask is important for your forum's security. Validating the input from a user can help ensure that data is not used in a way you do not expect. We have provided some simple regular expressions as hints.

"[A-Za-z]+" - Match all upper and lower case alphabet characters. "[0-9]+" - Match all numeric characters. "[A-Za-z0-9]{7}" - Match all upper and lower case alphabet and numeric characters seven times. "[^0-9]?" - Forbid any number from being matched. "^([A-Fa-f0-9]{3}|[A-Fa-f0-9]{6})$" - Only allow 3 or 6 character hexcodes.

Additionally, special metacharacters ?+*^$ and {xx} can be defined. ? - None or one match of previous expression. + - One or more of previous expression.

- None or more of previous expression.

{xx} - An exact number from previous expression. {xx,} - An exact number or more from previous expression. {,xx} - An exact number or less from previous expression. {xx,yy} - An exact match between the two numbers from previous expression. ^ - Start of string. $ - End of string. \ - Escapes the next character.

More information and advanced techniques may be found on the internet.

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Regular expressions: Difference between revisions From Online Manual

Revision as of 12:48, 11 June 2013

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-In Custom Profile Fields the Input Mask can be set to 'Regex (Advanced)', which then allows you to enter a regular expression that you would like to use to validate that profile field. However, the regex that you enter must be delimited by special characters. If you simply enter a regex, like this:
+Regular expressions can be used in the advanced profile fields/custom profile fields.
-[12][0-9]{3}
+The input mask is important for your forum's security. Validating the input from a user can help ensure that data is not used in a way you do not expect. We have provided some simple regular expressions as hints.
-it doesn't work. Even worse, it fails silently, acting as though '''any''' data that was entered is matched by the regex.
+"[A-Za-z]+" - Match all upper and lower case alphabet characters.
+"[0-9]+" - Match all numeric characters.
+"[A-Za-z0-9]{7}" - Match all upper and lower case alphabet and numeric characters seven times.
+"[^0-9]?" - Forbid any number from being matched.
+"^([A-Fa-f0-9]{3}|[A-Fa-f0-9]{6})$" - Only allow 3 or 6 character hexcodes.
-If you enter the regex surrounded by tildes, as shown by [http://www.simplemachines.org/community/index.php?topic=485300.msg3398080#msg3398080[emanuele]], or like this:
-~[12][0-9]{3}~
+Additionally, special metacharacters ?+*^$ and {xx} can be defined.
+? - None or one match of previous expression.
++ - One or more of previous expression.
+* - None or more of previous expression.
+{xx} - An exact number from previous expression.
+{xx,} - An exact number or more from previous expression.
+{,xx} - An exact number or less from previous expression.
+{xx,yy} - An exact match between the two numbers from previous expression.
+^ - Start of string.
+$ - End of string.
+\ - Escapes the next character.
-then it works as expected. Double quotes also work as delimiters.
-Tested in SMF 2.0.4.
+More information and advanced techniques may be found on the internet.