Forms and Form Data

Get versus Post

• The basic web browser and web server have two predifined methods for exchanging form data, the GET method and the POST method.
• With the GET method, the web browser embeds a long string onto the URL being passed back as an address to the web server.
• This string that is appended to the URL is then available for parsing by the CGI script that the server invokes.
• A sample URL resulting from a trivial GET form would be as follows:
  

  http://picocheep/cgi-bin/killbill/forms1.pl?TextfieldOne=I+entered+my+text+here
  

• An advantage of get data is that it can make it simple to link into documents from other locations, you just manually create the correct URL.
• A disadvantage of get data is that it can make the URL get awfully long, awfully ugly, and exposes a lot of your internal data.
• The POST method directs the web browser to establish a secondary connection with the web server, and to use that connection to transfer all fields and field data.
• The URL is short and clean, and the server manages the transfer of the web fields and field data.
• Disadvantages include the inability to cache data and the inability to manually build links that emulate filled out forms.
• Note that there are many other important architectural issues that should be considered when chosing GET or POST that are beyond the scope of this class.
• Note also that it makes precious little difference which you use in your Perl CGI script, they are all handled for you by Perl, and you only change one argument to one call. Both will likely do what you want done just fine, especially for the trivial cases will be dealing with.