湅楲潣倠汤-XMLNamespaces.pptVIP

XML Namespaces XML Namespaces What is Namespace? A namespace defines a new scope. Provide a way to avoid name collisions. What is XML Namespace? To give multiple elements of same name within the same document XML Namespace XML allows users to create own markup language for their own projects One such example is MathML (Mathematics Markup Language) MathML is derivative of XML MathML is used for displaying complex equations XML documents containing MathML tags in one single document. This is where XML Namespaces comes in Example ?xml version =“1.0”? MATH MIa/MI MIa/MI MIa/MI MIa/MI MIa/MI /MATH Conflicts In Name Base element name in MathML is MATH If any of element name in XML code uses MATH Compiler should know which of the MATH object should be treated to MathML instructions and which should be interpreted as XML markup This clearly shows Why we wanted Namespace and how scope of the name can be defined. Using Namespaces In C++ Declaring Namespace in C++ namespace direct { class Arrow { public: Arrow(int dir); void setDirection(int dir); private: int direction; } // ...... other stuff } Using Namespace using namespace direct; Direct.Arrow a = new Arrow(); Declaring Namespace In XML Syntax for declaring a namespace elementname xmlns:prefix =“namespaceurl” Namespace applied for MathML MATH xmlns:nm=/TR/REC-MathML” Explanation Of Using Namespace Prefix is used to identify that is associated with the element or attribute In XSL, either element name or attribute name after namespace prefix can be used to identify Namespace prefix is used with “xmlns” prefix to identify source of DTD used to identify universal attribute family Example ?xml version=“1.0”? MATH_ASSIGNMENT xmlns:mdoc=“/MATH/” mdoc:INSTRUCTIONS Solve the following…../mdoc:INSTRUCTIONS mdoc:Question id=“1” MATH xmlns:math=“/TR/REC-MathML” math:MIa/math:MI math:MO+/math:MO math:MIb/math:MI math:MO=/math:MO math:MIc/math:MI mdoc:INSTRUCTIONS Where A,B,C…… /mdoc:INSTRUCTIONS /MATH /mdoc:Question