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Multi Page Forms

Validate User Inputs

In order to combine a good user experience with maximum security, user inputs are validated in two steps.

The first validation is triggerd, when a user clicks the submit button, and is a browser side validation that uses Javascript. Aim of the browser side validation is, to display invalide inputs immediately to the user, in order to help them to fill the form correctly before it is submitted and the data are processed. Due to reasons which are beyond your reach, browser side validation may in some cases not work as expected, for example because the user has disabled Javascirpt on their browser or even circumvents the validation with code.

The second validation of the user inputs is performed on your server, after user inputs are submitted and send to the server. This validation is performed using php and kicks in before transmitted data are processed or stored in any other way. Other than browser side validation server side validation can not be manipulated or circumvented by the user. Server side validation protects your website by making sure that user inputs do really fit your specifications and are "clean". If server side validation detects invalide user inputs, Visforms will stopp processing the data and display the form again including error messages according to the invalide inputs. Valide inputs, which the user has already made, will be entered into the form by automatic action, then.

Supported Validation Types/Rules

Which kind of validation is available for a field depends on the field type. Please not, if you want to force a user to make a not empty input for a given field, you have to enable the validation option "Required" for this field. Any other validation type will only check, that a given user inputs has a proper format accoring to the validation rules set for the field but will accept an empty user input as valide.

If not indicated otherwise, all validation options are set in the field configuration tab "Basic Options".

Validation RuleDescriptionSupported in Field TypeAdditional Information
RequiredField cannot be left emptyAll field types except hidden fieldsPlease note: Only this validation rule forces a user to make an into
EmailCheck for a valide email address format.
  • Email
Field type specific validation, which will be applied to any field of type e-mail by automatic action.
UrlCheck for a valide url address format that starts with http.
  • Url
Field type specific validation, which will be applied to any field of type url by automatic action.
NumberChecks for a valide number
  • Number
Field type specific validation, which will be applied to any field of type number by automatic action.
DateChecks the user input against the date format selected in the field configuration
  • Date
Field type specific validation, which will be applied to any field of type date by automatic action. Suported date formats are: DD.MM.YYYY, MM/DD/YYYY and YYYY-MM-DD
Minimum Length"Text" fields: Minimal number of characters a user has to type in.

Checkbox Group: Minimal number of checkbox controls the user has to check.
  • Text
  • Password
  • Email
  • Url
  • Textarea
  • Checkbox Group
If you have enabled the use of "HTML-Editor" for a field of type "Textarea" the number of charachters added by the user is sometimes evaluated incorrect (to big).
Maximum Length"Text" fields: Maximum number of characters a user can type in.

Checkbox Group: Maximum number of checkbox controls the user can check.
  • Text
  • Password
  • Email
  • Url
  • Textarea
  • Checkbox Group
If you have enabled the use of "HTML-Editor" for a field of type "Textarea" the number of charachters added by the user is sometimes evaluated incorrect (to big).

If you do not set this option for a Checkbox Group, a user can check all checkboxes.
Minimum valueLowest number possible.
  • Number
Maximum valueHighest number possible.
  • Number
Minimum Date ValueEarliest date value allowed . This validation value can be set as:
  • Fixed date
  • A date relative to the current date (plus/minus n days)
  • A date relative to the user input in another date field (plus/minus n days)
  • Date
You need a Visforms Subscription, if you want to use this validation rule.
Maximum Date ValueHighest date value allowed . This validation value can be set as:
  • Fixed date
  • A date relative to the current date (plus/minus n days)
  • A date relative to the user input in another date field (plus/minus n days)
  • Date
You need a Visforms Subscription, if you want to use this validation rule.
Digits onlyAllow digits only. No negative numbers, no decimals...
  • Number
Custom validationPerform a custom validation as defined by an individual regular expression.
  • Text
  • Password
  • Email
  • Number
  • Url
  • Textarea
Allow multiple selectionA user can select more than one option at a time.
  • Select
The default behavior, when this option is disabled, is, that a user can only select one option.
Equal toUser input in two (or more) fields have to be identical.
  • Text
  • Password
  • Email
  • Date
  • Number
  • Url
Fields, used for "Equal to" validation must be of the same field type.
Allowed File ExtensionsAllowed File Extension(s) for files that can be uploaded with the field.
  • File Upload
File Upload Maximum SizeMaximum file size of files that can be uploaded with the form.
  • File Upload
This option is set in the form configuration tab "Advanced".
Unique values onlyThe form can only be submitted, if a given value for this field does not already exist in a recordset that was submitted for this form previously.
  • Text
  • Password
  • Email
  • Date
  • Number
  • Url
  • hidden
  • Textarea
  • Checkbox
  • Checkbox Group
  • Radiobutton
  • Select
This validation option is set in the field configuration tab "Advanced". It can only be performed if user inputs are stored in the database. (Which is trigged by the form option "Save Results" which is set in the form configuration tab "Result".) Validation for "Unique values only" is only performed server side.

Visforms uses the jQuery Validator Plugin for browser side validation.

Visforms allows you to create custom error messages, which will be used in the broweser side validation, if user inputs are not valide. If no custom error message is set, Visforms will use the default error messages. If the validation of user inputs fails on server side valiation and the form is displayed again, Visforms will always use default error messages. You can use the Joomla! language manager in order to customize the default error messages, if need be.

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