presence

Check if an input has been filled in or checked.

For example when a title must be entered:

<input type="text" id="title" name="title" value="" />
{% validate id="title" type={presence} %}

Arguments

Argument	Description	Example
`failure_message`	Message to be shown when field is empty. Defaults to “*”	`failure_message="Please enter."`

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postback Validators json

postback Forms and validation username_unique

Referred by

Developer guide

Forms and validation

You should validate all input data entered in forms. In Zotonic you create forms by writing plain HTML. You can attach one or more validators to each input…

acceptance

Check if an input value evaluates to true.

validate

The validator tag accepts the following arguments:

postback

Performs a custom server side validation of an input value. This allows you to add your own validation logic to HTML form fields.

custom

Support for custom client-side (JavaScript-based) validators.

confirmation

Check if two inputs are the same.

page_path_unique

A validator to check whether a resource’s page path is unique:

hasedge

A validator to check if a resource has a certain number of edges with a predicate.

acceptable_password

A validator to check whether a password conforms to the password secutiry requirements.

json

Validate that a form value is JSON.

Type at least two characters

presence

Arguments

Referred by

Related documentation