XSD any element of any order as many times as you like

Question

I tried everything <xs:all>, <xs:choice>, and <xs:sequence>

None of them satisfactorily help my cause.

Does anyone know how you would confirm something like that.

<Menu>  
   <SubMenu>
      <MenuItem .. />  
      <MenuItem .. />  
      <MenuItem .. />  
   </SubMenu>  
   <MenuItem .. >  
   <MenuItem .. >  
</Menu>

Where, In the tag <Menu>  <SubMenu>and / or <MenuItem>may occur any number of times (0-n) in any order. But at least one of them must happen at least once.

Ignoring checks inside SubMenu tags.

Thank any help in this matter.

Answer 1

, " SubMenu MenuItem, SubMenu MenuItem". :

<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">

    <!-- whatever your element needs to be modelled as here -->
    <xs:element name="MenuItem">
        <xs:complexType>
            <xs:attribute name="text"/>
        </xs:complexType>
    </xs:element>

   <!-- only modelling the structure of the child elements here -->
    <xs:element name="SubMenu">
        <xs:complexType>
            <xs:sequence>
                <xs:choice minOccurs="1" maxOccurs="1">
                    <xs:element ref="MenuItem"/>
                    <xs:element ref="SubMenu"/>
                </xs:choice>
                <xs:choice minOccurs="0" maxOccurs="unbounded">
                    <xs:element ref="MenuItem"/>
                    <xs:element ref="SubMenu"/>
                </xs:choice>
            </xs:sequence>
        </xs:complexType>
    </xs:element>

    <xs:element name="Menu">
        <xs:complexType>
            <xs:sequence>
                <xs:choice minOccurs="1" maxOccurs="1">
                    <xs:element ref="MenuItem"/>
                    <xs:element ref="SubMenu"/>
                </xs:choice>
                <xs:choice minOccurs="1" maxOccurs="unbounded">
                    <xs:element ref="MenuItem"/>
                    <xs:element ref="SubMenu"/>
                </xs:choice>
            </xs:sequence>          
        </xs:complexType>
    </xs:element>
</xs:schema>

, SubMenu, , .