Adding an include element

As schemas become larger, it is often desirable to divide their content among several schema documents for purposes such as ease of maintenance, reuse, and readability. XML schema defines two constructs to support this: include and import. The include element brings in definitions and declarations from the included schema into the current schema. It requires the included schema to be in the same target namespace as the including schema. The import element behaves in a similar way, with the exception that the imported schema can come from a different namespace.

In the XML schema editor, you can add an include element to an XML schema. Before you can do this, create an XML schema and open it in the XML schema editor (you can open an XML schema in the XML schema editor by double-clicking it).

The following instructions were written for the XML perspective, but they will also work in many other perspectives.

To add an include element ,...

  1. Open your XML schema in the XML schema editor.

  2. In the Outline view, select your schema. The entire schema and its contents should be displayed in the Graph view.

  3. In the Graph view, right click in the Directives section and click Add Include.

  4. In the Properties view, click the General tab and click the More button to the right of the Schema location field. The XML schema file you select must have the same namespace as the current schema.

  5. If you want to select an XML schema located in the workbench, select the Workbench projects radio button and click Next.

    1. Select the schema you want to include and click Finish.

  6. If you want to select an XML schema located on the Web, select the HTTP radio button and click Next.

    1. Type the URL of the XML schema and click Finish.

    Note: A local copy of the schema will not be stored in the workbench. Every time you validate your schema, the schema's contents will be checked from the URL you specify.

  7. The XML schema editor will retrieve the location of the included XML schema file and display it as read-only in the Schema location field.

  8. Click the Documentation tab if you want to provide any information about this include element. The Documentation page is used for human readable material, such as a description, and the App Info page can be used to provide information for applications.

Once you have added the include element to your XML schema, when you define new elements, attributes, complex types, or simple types where you can specify type information, any declarations from the included schema will be available in the Type list for the element, attribute, complex or simple type.

For example, if Address.xsd has the following content:

<complexType name="Address">
    <sequence>
        <element name="name" type="string">
        <element name="street" type="string">
    </sequence>
</complexType>
and you have an XML schema called PurchaseOrder.xsd that has added an include for Address.xsd, then when defining a new element in PurchaseOrder, you can select Address as its type.

(c) Copyright 2001, World Wide Web Consortium (Massachusetts Institute of Technology, Institut National de Recherche en Informatique et en Automatique, Keio University).

 

Related tasks

Adding an import element
Adding a redefine element

Related reference
XML namespaces