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Elements with a Nillable Attribute
, version 5.0 only, fully supports nillable element attributes in schema. In previous versions, a required field (minOccurs = 1 or greater) in a form generated from schema, HAD to have a value for the form to be submitted. The control was considered required, ie. the control would display a yellow background color. Nillable attributes override the fact that the field is required and, if present and set to true, required controls will now be considered optional. When you submit a form and do NOT have a value in a minOccurs > 0 nillable field, the XML document generated by will contain an EMPTY element like this <control name xsi:nil="true"/>.
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