With XML Schemas, one element can substitute another element.
Let's say that we have users from two different countries: England and Norway. We would like the
ability to let the user choose whether he or she would like to use the India element names or
the English element names in the XML document.
To solve this problem, we could define a substitutionGroup in the XML schema. First, we
declare a head element and then we declare the other elements which state that they are
substitutable for the head element.
In the example above, the "name" element is the head element and the "navn"
element is substitutable for "name".
Look at this fragment of an XML schema:
A valid XML document (according to the schema above) could look like this:
or like this:
To prevent other elements from substituting with a specified element, use the block
A valid XML document (according to the schema above) looks like this:
BUT THIS IS NO LONGER ValiD:
The type of the substitutable elements must be the same as, or derived from, the type of the head
element. If the type of the substitutable element is the same as the type of the head element
you will not have to specify the type of the substitutable element.
Note that all elements in the substitutionGroup (the head element and the substitutable elements)
must be declared as global elements, otherwise it will not work
Global elements are elements that are immediate children of the "schema" element! Local
elements are elements nested within other elements.
Your Query was successfully sent!