Breaking News
yeni film izle hd film seyret film izle

DTD Attributes IN XML

In the DTD, XML element attributes are defined with an ATTLIST declaration.
An attribute declaration has the following syntax:
<!ATTLIST element-name attribute-name attribute-type default-value>
Tthe ATTLIST declaration defines the element which can have the attribute, attribute-name is the name of the attribute, attribute-type is the type of the attribute, and the default attribute value.
The attribute-type can have the following values:
Value Explanation
xml: The value is predefined
ID The value is an unique id
IDREF The value is the id of another element
IDREFS The value is a list of other ids
CDATA The value is character data
NMTOKEN The value is a valid XML name
NMTOKENS The value is a list of valid XML names
ENTITY The value is an entity
ENTITIES The value is a list of entities
NOTATION The value is a name of a notation
(eval|eval|..) The value must be an enumerated value
The default-value can have the following values:
Value Explanation
#DEFAULT value The attribute has a default value
#REQUIRED The attribute value must be included in the element
#IMPLIED The attribute does not have to be included
#FIXED value The attribute value is fixed
Attribute declaration example:
<?xml version=”1.0″ encoding=”ISO-8859-1″?>
<!DOCTYPE email [
  <!ELEMENT email (sender,recipient,subject,message)>
   <!ATTLIST email priority CDATA “normal”>
<email priority=’high’>
In the above example, the element email is defined to be an empty element with the attributes propriety of type CDATA. The priority attribute has a default value of “Normal”.
Click here to view the example.
Enumerated attribute values
<!ATTLIST element-name attribute-name (eval|eval|..) default-value>
DTD example:
<!ATTLIST payment mode (check|cash) “cash”>  
XML example:
<payment mode=”check”>
<payment mode=”cash”> 
Use enumerated attribute values when you want the attribute values to be one of a fixed set of legal values.
Fixed attribute value
<?xml version=”1.0″ encoding=”UTF-7″?>
<!DOCTYPE ebiz [
   <!ELEMENT ebiz (associate_details,emp_details,sponser_details)>
   <!ATTLIST ebiz companysite CDATA #FIXED “”>
Use a fixed attribute value when you want an attribute to have a fixed value that the author can not change. If an author includes another value, the XML parser will return an error.
Required attribute
<!ELEMENT payment (amount+,duration+)>
     <!ATTLIST payment mode CDATA #REQUIRED>
XML example:
<payment mode=”cash”></payment>
Use a required attribute if you don’t have an option for a default value, but still want to force the attribute to be present. The required (#REQUIRED) attribute force the document author to use the attribute.
Implied attribute
<!ELEMENT addressdetails (address+,city?,state,pin)>
     <!ATTLIST addressdetails communication_mode CDATA #IMPLIED>
      <addressdetails communication_mode=”post”>
Use an implied attribute if you don’t want to force the author to include an attribute and you don’t have an option for a default value either.

Check Also

XML and Server

Generating XML with JSP   XML can be generated on a server without any installed …