12 1 Redirection CGI/Perl Programming By Diane Zak

12 2 Objectives In this chapter, you will: Include the Location header in a script Include the Refresh header in a script

12 3 Introduction Documents often move on the Web from one location to another –Link to new URL so user must click to go to new location –Automatically forward the browser to a new address Immediately After a period of time (seconds) –META tag – HTML –Location Header – script –Refresh Header - script

12 4 Redirecting a browser Location header: –Immediately redirects the browser –Syntax: print “Location: url\n\n”; –Example: print “Location: The 1 st newline character identifies the end of the Location header The 2 nd newline character inserts a blank line below the header to signal end of header section Location header used instead of Content-type header

12 5 Redirecting a Browser Refresh header: –Waits a specified number of seconds before redirection –Syntax: print “Refresh: seconds; URL=url\n”; –Example: print “Refresh: 3; URL=“ print “Content-type: text/html\n\n”; Contains one newline character because it is used with the Content-type header

12 6 Using a Refresh Header

12 7 Using a Refresh Header Uses Refresh header to redirect the page in 3 seconds

12 8 Using a Location Header

12 9 Using a Location Header If no Name was typed into the cara1.html page

12 10 Summary You can use the Location header or the Refresh header in a CGI script to redirect the user’s browser to another location. The Location header redirects the browser immediately. –Syntax: print “Location: url\n\n”; The Refresh header waits for a specified number of seconds until redirection. –Syntax: print “Refresh: seconds; URL=url\n”; –Is used together with the Content-type header