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XForms Properties

XForms properties define data restrictions, types and behaviors.

XForms uses properties to define restrictions (or other attributes) that can affect the behavior of XForms controls.

Examples:

A required="true()" property will not allow the specified instance data to be submitted as an empty value.

A type="decimal" property will only allow a decimal value to be submitted.

A calculate property can calculate a value for the instance data.

Please refer to the properties reference at the bottom of this page.

Binding Properties To Data

XForms uses the <bind> element to bind XForms properties to XForms data:

<model>
<instance>
  <person>
      <fname/>
      <lname/>
  </person>
</instance>
<bind nodeset="person/lname" required="true()"/>
</model>

In the example above, the attribute nodeset="person/lname" binds the property required="true()" to the instance data element <lname>.

Name	Description
calculate	Defines a calculation to be performed on the item
constraint	Defines a constraint for the item
p3ptype	Defines a P3P data type for the item
readonly	Defines an edit restriction for the item (cannot be changed)
relevant	Defines how relevant the data is (for display or submission)
required	Defines if data item is required (cannot be blank)
type	Defines the data type for the item