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Chapter 2 Building an XML model
Child elements are linked to their parent element through a group particle.
Defining group particles
Group particles indicate how child elements are related with their parent element.
You can choose a group particle from the following list:
Tool | Tooltip | Description |
| Sequence | Child elements must appear at least once in the order of |
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| their declaration |
| Choice | Only one child element can be linked to the parent |
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| element |
| All | Child elements can appear in any order and each of |
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| them once or not |
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In a schema, a group particle is declared with its corresponding tag: <sequence>, <choice> or <all>.
Group particles in | In a model targeted with the | ||
XDR files | are declared through the order attribute of an <ElementType> tag: | ||
| Group particle |
| Value of the order attribute in XDR |
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| Sequence |
| seq |
| Choice |
| one |
| All |
| many |
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Extract of an XDR file:
XSM User's Guide | 53 |