Xml namespace
- 2. What is XML ?
- 3. What is Namespace ? A namespace is a set of unique names. Namespace is a mechanisms by which element and attribute name can be assigned to a group. The namespace is identified by uri(uniform resource identifiers).
- 4. Syntax The Namespace starts with the keyword xmlns. The word name is the Namespace prefix. The URL is the Namespace identifier. <element xmlns:name=“url”>
- 5. XML Namespace <authors> <author book type=“Classical”> <title>web</title> <type>technology</type> </author> </author> <html> <head> <title>web technology</title> </head> <body> ……… …….. </body> </html>
- 6. Define elements and attributes that can be reused in other schemas or instance documents without fear of name collisions. Combine fragments from different documents without any naming conflicts. Write reusable code modules that can be invoked for specific elements and attributes ADVANTAGES
- 7. Namespace allow the browser to: Combine various sources of document It helps to identify the source of elements or attributes UNIFORM RESOURCE LOCATOR(url): contains a reference for a document or an html page on the web <?xml version = "1.0" encoding = "UTF-8"?> <sample xmlns:cont = "www.abcd.com"> <cont:name>Gayathri</cont:name> <cont:company>abcd</cont:company> <cont:phone>123-4567</cont:phone> </cont:contact>
- 8. Example for Namespace <bk:authors xmlns:bk=“http://abcd.com”> <bk:author book type=“classical”> <bk:title>web</bk:title> <bk:type>technology</bk:type> </bk:author> </bk:author> We have added the xmlns: (prefix) attribute to the root element. We have assigned this attribute a unique value. This unique value is usually in the form of a url. This defines a namespace. And now that the namespace that have been defined ,we have added a bk prefix to our eelement names. Now when we combine the two documents, the xml processor will see two different element names: bktitle(from the xml document) and title(from the html document).
- 9. LOCAL NAMESPACE OLD <bk:author xmlns:bk=“www.abcd.com”> <bk:author booktype=“classical”> <bk:title>web</bk:title> <bk:type>technology</bk:type> </bk:author> </bk:author> New <author xmlns:bk=“www.abcd.com”> <author booktype=“classical”> <bk:title>web</bk:title> <type>technology</type> </author> </author> Name conflict happened only for title tag Add Namespace only for title tag
- 10. Multiple Name Space <bk:author xmlns :bk=“www.abcd.com”> <bk:author booktype=“classical”> <bk:title>web</bk:title> <bk:type>technology</bk:type> <pub:author xmlns pub=“www.efg.com”> </pub:author> </bk:author> </bk:author> Name Space 1 bk Name Space 2 pub