XSD Composite Type Indicator

xsd mixed content xsd <any>

With an indicator, we can control how elements are used in a document. Indicator

There are seven kinds of indicators: Order Indicator: all Choice Sequence occurrence indicator : maxOccurs minOccurs Group indicator: Group Nam E attributegroup name Order indicator

The order indicator is used to define the sequence of elements. All indicator

The <all> indicator specifies that child elements can appear in any order, and that each child element must appear only once:

<xs:element name= "Person" >
  <xs:complexType>
    <xs:all>
      <xs:element name= " FirstName "type=" xs:string "/>
      <xs:element name=" LastName "type=" xs:string "/>
    </xs:all>
  </xs:complexType>
</xs:element>

Note: When using the <all> indicator, you can set the <minOccurs> to 0 or 1, but only the <maxOccurs> indicator to 1 (will be explained later <minOccurs> and <m axoccurs>). Choice Indicator

The <choice> indicator specifies that a child element may appear or another sub-element may appear (either):

<xs:element name= "Person" >
  <xs:complexType>
    <xs:choice>
      <xs:element name= " Employee "type=" employee "/>
      <xs:element name=" member "type=" member "/>
    </xs:choice>
  </xs:complexType>
</xs:element>

Tip: If you want to set child elements to occur any number of times, you can set <maxOccurs> (explained later) to unbounded (unlimited). Sequence Indicator

<sequence> specifies that child elements must appear in a specific order:

<xs:element name= "Person" >
  <xs:complexType>
    <xs:sequence>
      <xs:element name= " FirstName "type=" xs:string "/>
      <xs:element name=" LastName "type=" xs:string "/>
    </xs:sequence >
  </xs:complexType>
</xs:element>

Occurrence Indicator

The occurrence indicator is used to define how often an element appears.

Note: For all "Order" and "group" indicators (any, all, choice, sequence, group name, and group reference), the default values for MaxOccurs and minOccurs are 1. maxOccurs Indicator

The <maxOccurs> indicator can specify the maximum number of times an element can occur:

<xs:element name= "Person" >
  <xs:complexType>
    <xs:sequence>
      <xs:element name= " Full_name "type=" xs:string "/>
      <xs:element name=" Child_name "type=" xs:string
    "maxoccurs="/> </xs:sequence>
  </xs:complexType>
</xs:element>

The above example shows that the child element "Child_name" can appear at least once in the "person" element (where the default value of MinOccurs is 1) and occurs up to 10 times. minOccurs Indicator

The <minOccurs> indicator can specify the minimum number of times an element can occur:

<xs:element name= "Person" >
  <xs:complexType>
    <xs:sequence>
      <xs:element name= " Full_name "type=" xs:string "/>
      <xs:element name=" Child_name "type=" xs:string "
      maxoccurs=" 10 " minoccurs= "0"/>
    </xs:sequence>
  </xs:complexType>
</xs:element>

The above example shows that the child element "Child_name" can appear at least 0 times in the "person" element, up to 10 times.

Tip: If you want to make an element appear unlimited, use the maxoccurs= "unbounded" statement: A practical example:

XML file named "Myfamily.xml":

<?xml version= "1.0" encoding= "iso-8859-1"?> <persons

xmlns:xsi= "http://www.w3.org/2001/ Xmlschema-instance "
xsi:nonamespaceschemalocation=" family.xsd ">

<person>
<full_name >tony smith</full_name>
<child_name>Cecilie</child_name>
</person>

< person>
<full_name>david smith</full_name>
<child_name>Jogn</child_name>
<child_name>mike</child_name>
<child_name>kyle</child_name>
<child_ name>mary</child_name>
</person>

<person>
<full_name>michael Smith </full_name>
</person>

</persons>

The above XML file contains a root element named "persons". Within this root element, we have defined three "person" elements. Each person element must contain a "full_name" element, and it can contain as many as 5 "child_name" elements.

This is the schema file "family.xsd":

<?xml version= "1.0" encoding= "iso-8859-1"?> <xs:schema
xmlns:xs= "Http://www.w3.org/2001/XMLSchema"
elementformdefault= "qualified" >

<xs:element name= "Persons" >
  <xs:complexType>
    <xs:sequence>
      <xs:element name= "person" maxoccurs= "unbounded" >
        <xs:complexType>
          <xs:sequence>
            <xs:element name= "full_name" type= "xs:string"/> <xs:element
            name= "Child_name "Type=" xs:string "
            minoccurs=" 0 "maxoccurs=" 5 "/>
          </xs:sequence>
        </xs:complexType>
      </xs:element>
    </xs:sequence>
  </xs:complexType>
</xs:element>

</xs:schema>

Group Indicator

The Group indicator is used to define the relevant batch elements. Element Group

Element groups are defined by the Group declaration:

<xs:group name= "group name" >
  ...
</xs:group>

You must define an all, choice, or sequence element within the group declaration. The following example defines a group named "Persongroup", which defines a set of elements that must appear in an exact order:

<xs:group name= "Persongroup" >
  <xs:sequence>
    <xs:element name= "FirstName" type= "xs:string"/ >
    <xs:element name= "LastName" type= "xs:string"/>
    <xs:element name= "Birthday" type= "xs:date"/ >
  </xs:sequence>
</xs:group>

After you have defined the group, you can reference it in another definition:

<xs:group name= "Persongroup" >
  <xs:sequence>
    <xs:element name= "FirstName" type= "xs:string"/ >
    <xs:element name= "LastName" type= "xs:string"/>
    <xs:element name= "Birthday" type= "xs:date"/ >
  </xs:sequence>
</xs:group>

<xs:element name= "person" type= "Personinfo"/>

<xs:complextype name= "Personinfo" >
  <xs:sequence>
    <xs:group ref= "Persongroup"/>
    <xs:element name= "Country" type= "xs:string"/>
  </xs:sequence>
</xs:complexType>

attribute Group

Attribute groups are defined by the AttributeGroup declaration:

<xs:attributegroup name= "group name" >
  ...
</xs:attributeGroup>

The following example defines an attribute group named "Personattrgroup":

<xs:attributegroup name= "Personattrgroup" >
  <xs:attribute name= "FirstName" type= "xs:string"/>
  <xs:attribute name= "LastName" type= "xs:string"/>
  <xs:attribute name= "Birthday" type= "xs:date"/>
</xs:attributeGroup>

After you have defined the attribute group, you can reference it in another definition, like this:

<xs:attributegroup name= "Personattrgroup" >
  <xs:attribute name= "FirstName" type= "xs:string"/>
  <xs:attribute name= "LastName" type= "xs:string"/>
  <xs:attribute name= "Birthday" type= "xs:date"/>
</xs:attributeGroup>

<xs:element name= "Person" >
  <xs:complexType>
    <xs: attributegroup ref= "Personattrgroup"/>
  </xs:complexType>
</xs:element>