restricts passwords to 8+ characters

Match a not-empty string. A string with only spaces or no characters is an empty-string. When match something, mathc all the string with the exception of the eventually space at the and

get the file extension of a given filename

поиск в тексте всех ссылок на профили пользователей вконтакте. ссылки вида [id12345678|Name]

List of EmailAddresses optionally allowing with personal i.e. "Personal Name "

This string can help you locate/select the last underscore in a string

Valida se é um CPF ou um CNPJ válido, independente da máscara

Selects Xml version and Encoding and whitespaces

Pattern that check your string to match Facebook user profile URL.

Valida las posibles respuestas al insertar una pregunta, esto se realiza ya que las respuestas se ordenan aleatoriamente, por eso no se permite respuestas del tipo "A y B son correctas"

phone number without spaces or hyphens +7YYYXXXXXXX