Validation (regular expressions)

Each entry field in a form can be validated directly during entry  with the help of a regular expression. Openforms supports Java regular expression to this end. In addition to the examples displayed below the website can be helpful.

Validation using the example of a textfield

  • In the configuration area of a text box there is the possibility of selecting prefabricated regular expression from a dropdown menu.
  • In the box to the right you may also formulate your own regular expressions.
  • The Java Regex Syntax is to be followed
  • Directly underneath the selection for the regular expression there is a dropdown for the selection of a special validation component. The special validation components are specific to certain projects and therefore not available in every openforms version. .
    Here you may select from implemented more complex validations, e.g.:

            • EmailDNSValidation (the domain is verified)
            • IBAN Validator (checksum of the IBAN is verified) 
            • Abbreviation (Validates whether names were for example entered in the form " Max A. Mustermann" )


Examples for Regular Expressions

FieldValidation and ExplenationExplenation

The expression is divided into three part. Before the @ numbers, upper case and lower case letters, underscores, minus and full stop are allowed. Behind the the same rule applies. This is followed by a period. After the period  sind Zahlen, Groß- und Kleinbuchstaben ohne Umlaute, Unterstriche, Minus und . erlaubt. Hinter dem @ gilt exakt die gleiche Regel. Es folgt ein Punkt. Nach dem Punkt müssen noch mindestens 2 maximal 5 Buchstaben (groß oder klein) kommen. 

Das Symbol ^ bestimmt das die Eingabe vor dem @ mit den danach genannten zeichen erfolgen muss

Das Symbol $ bedeutet das die Eingabe mit den vor $ genannten Zeichen enden muss

Phone[\+0][0-9 /\-]+
The signs / and + can be used once at most. All numbers can be used once or numerous times.
First Name[a-zA-Z \-.,()+/?:'ÄäÖöÜüß]{1,35}
All signs may be used with the exception of brackets. There has to be a minimum of one sign and a maximum of 35 signs.