Web Client Programming with Perl-Chapter 7: Graphical Examples with Perl/Tk- P1

... Chapter 7: Graphical Examples with Perl/Tk- P1 The Tk extension to Perl can be used to create a Graphical User Interface (GUI) to your Perl programs ... show a few examples of Tk-based web clients, which go beyond the command-line interface that we've been using so far in this book:[1]  xword, a dictionary client  track, a graphical version ... simple program that...

Ngày tải lên: 07/11/2013, 09:15

... Chapter 7: Graphical Examples with Perl/Tk- P2 The do_search( ) function will take an optional $url argument, to give ... we need to delimit it from the prior text (which we insert into our text widget with the flush_text( ) function) with a few returns. Note that flush_text( ) takes the same arguments as any of ... to call our function, do_search( ), with the URL we extracted...

Ngày tải lên: 07/11/2013, 09:15

... Chapter 7: Graphical Examples with Perl/Tk- P3 Our destinations list is an almost exact copy of the list you'd see on the web page. For ease in using, we placed ... going to use a default of today for the date field. The FedEx web page expects it in the form of "DayMonthYear", and digits with only one number require a leading zero. The string returned ... letter...

Ngày tải lên: 07/11/2013, 09:15

... Chapter 7: Graphical Examples with Perl/Tk- P4 Check if Servers Are up: webping For the last example, we'll build a GUI interface that will allow us to check and see if several web sites ... similar to the UNIX ping command, we call it webping. This application would be useful to a web administrator who had to keep track of many different web sites, and wanted to k...

Ngày tải lên: 14/12/2013, 13:15

... header. Clients use this information to correctly handle the media type and format of the entity- body. A client might also use a Content-type header with the POST or PUT method. Most commonly, with ... If-Modified-Since, et al. To accommodate client- side caching of documents, the client can use the If- Modified-Since header with the GET method. When using this option, the client...

Ngày tải lên: 17/10/2013, 19:15

... it's not fully compliant with the HTTP specs, the web server won't understand you! Perhaps your web client works with one web server but not another. Or maybe your web client works most of the ... and map a client& apos;s incoming request to a file handle. After a client request has been accepted, all subsequent communication with the client is referenced thro...

Ngày tải lên: 20/10/2013, 10:15

... Socket; # include Socket module require 'tcp.pl'; # file with Open_TCP routine require &apos ;web. pl'; # file with parseURL routine use vars qw($opt_h $opt_H $opt_r $opt_d); use ... network connection close(F); } Shell Hypertext cat With hcat, one can easily retrieve documents from remote web servers. But there are times when a client request needs to be more complex...

Ngày tải lên: 20/10/2013, 10:15

... that are useful for client programming. The LWP Module The LWP module, in the context of web clients, performs client requests over the network. There are 10 classes in all within the LWP module, ... module describes client requests, server responses, and dates, and computes a client/ server negotiation.  The LWP module is the core of all web client programs. It allows the cli...

Ngày tải lên: 24/10/2013, 08:15

... In the context of web client programming, you'll usually get an HTTP::Response object from LWP::UserAgent and LWP::RobotUA. If you plan to write extensions to LWP or a web server or proxy ... as a scalar. $r->code([$code]) When invoked without any parameters, the code( ) method returns the object's response code. When invoked with a status code as the first parameter, co...

Ngày tải lên: 24/10/2013, 08:15

... that a client may exhibit. The examples in this chapter all use a simple command-line interface. In Chapter 7, Graphical Examples with Perl/Tk, we have some additional examples with a graphical ... programs with more user-friendly options and features. We present three broad categories of web client programs:  Simple clients--programs that perform actions for users in r...

Ngày tải lên: 28/10/2013, 15:15