dynamic attribute definition in xsd

[Anoop Krishnan]

I have an Element called Parameter with several attribute (See Code block 1:).
The attribute type is enumerated (See Code block 2 : the simpleType definition DataType)
I want to achieve the following constrain.

The attributes "value" and "source" should not appear together

The attribute "value" is valid only when attribute "type" has a value "StaticEnum"

The attribute "source" is valid only when attribute "type" has a value "Fid"

How can I define the constrain for every Parameter Element.

<xs:element name="Parameter" minOccurs="0"
maxOccurs="unbounded">
<xs:complexType>
<xs:sequence>
<xs:element name="Fragment"
minOccurs="0" maxOccurs="1">
<xs:complexType
mixed="true">
<xs:attribute
name="insertat" type="xs:string" use="optional">
</xs:attribute>
</xs:complexType>
</xs:element>
</xs:sequence>
<xs:attribute name="name"
type="xs:string" use="required">
</xs:attribute>
<xs:attribute name="type"
type="ng:DataType" use="required">
</xs:attribute>
<xs:attribute name="value"
type="xs:string" use="optional">
</xs:attribute>
<xs:attribute name="source"
type="xs:string" use="optional">
</xs:attribute>
<xs:attribute name="outputFormat"
type="xs:string" use="optional">
</xs:attribute>
<xs:attribute name="multi"
type="xs:boolean" use="optional" default="false">
</xs:attribute>
<xs:attribute name="required"
type="xs:boolean" use="optional" default="false">
</xs:attribute>
<xs:attribute name="final"
type="xs:boolean" use="optional" default="false">
</xs:attribute>
<xs:attribute name="mapto"
type="xs:string" use="optional">
</xs:attribute>
<xs:attribute name="insertat"
type="xs:string" use="optional">
</xs:attribute>
<xs:attribute name="description"
type="xs:string" use="optional">
</xs:attribute>
<xs:attribute
name="typeValueSwapper" use="optional" type="xs:string">
</xs:attribute>
</xs:complexType>
</xs:element>

<!-- Data Types for Fids & Parameters -->
<xs:simpleType name="DataType">
<xs:restriction base="xs:string">
<xs:enumeration value="String"></xs:enumeration>
<xs:enumeration value="Char"></xs:enumeration>
<xs:enumeration value="Integer"></xs:enumeration>
<xs:enumeration value="Float"></xs:enumeration>
<xs:enumeration value="StaticEnum"></xs:enumeration>
<xs:enumeration value="RuntimeEnum"></xs:enumeration>
<xs:enumeration value="DateTime"></xs:enumeration>
<xs:enumeration value="Boolean"></xs:enumeration>
<xs:enumeration value="Fid"></xs:enumeration>
<xs:enumeration value="Image"></xs:enumeration>
<xs:enumeration value="Color"></xs:enumeration>
</xs:restriction>
</xs:simpleType>

[ November 11, 2008: Message edited by: Anoop Krishnan ]
[ November 11, 2008: Message edited by: Anoop Krishnan ]