Variable parsing - Dev Shed

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July 26th, 2000, 01:45 AM

jgagner

Contributing User

Join Date: Jul 2000

Location: Seattle, WA,USA

Posts: 84

Time spent in forums: < 1 sec
Reputation Power: 9

I was wondering if there was a better way of collecting variables thatn the code I'm using now. I guess I would use this command "use CGI", but I have no Idea what that is. There is probably some really simple solution, as always in perl. Here's the code I use now (kinda complicated :confused )

%postInputs = readPostInput();
... #omitted

sub readPostInput(){
my (%searchField, $buffer, $pair, @pairs);
if ($ENV{'REQUEST_METHOD'} eq 'POST') {
read(STDIN, $buffer, $ENV{'CONTENT_LENGTH'});
@pairs = split(/&/, $buffer);
foreach $pair (@pairs) {
($name, $value) = split(/=/, $pair);
$value =~ tr/+/ /;
$value =~ s/%([a-fA-F0-9][a-fA-F0-9]/pack("C",
hex($1))/eg;
$name =~ tr/+/ /;
$name =~ s/%([a-fA-F0-9][a-fA-F0-9])/pack("C",
hex($1))/eg;
$searchField{"$name"} = $value;
}
}
return (%searchField);
}

...#end of program

July 26th, 2000, 06:02 AM

Shiju Rajan

.Net Developer

Join Date: Feb 2000

Location: London

Posts: 987

Time spent in forums: 3 h 26 m 22 sec
Reputation Power: 9

<< I guess I would use this command "use CGI", but I have no Idea what that is. >>

yea, you can use CGI.pm module in your cgi program so your form parsing would be very easy.

see this example...

test.html
----------

<html>
<head>
<title>Test</title>
</head>
<body bgcolor="#FFFFD9">
<form method="post" action="test.cgi">
Name : <input type="text" name="name">
<br>
<input type="submit" value="submit">
</form>
</body>
</html>

test.cgi
--------

#!/usr/bin/perl

use CGI;
#use cgi.pm module..

$q=new CGI;

#initialize the cgi.pm..

$name=$q->param('name');

# get the name value from the form..

print $q->header;

#print page header..

print "Hello ".$name."n";

----------------------

That is it...

------------------
SR -
webshiju.com

"The fear of the LORD is the beginning of knowledge..."

July 26th, 2000, 09:50 AM

ledjon

Guest

Posts: n/a
Time spent in forums:
Reputation Power:

I don't really like to use the CGI.pm unless I'm doing something like uploading an image. I'll explain your code so that it's not so confusing, but you really don't need to know what it does.:
##########
#Optional If stament.
if ($ENV{'REQUEST_METHOD'} eq 'POST') {

#Read's the POSTed data.
read(STDIN, $buffer, $ENV{'CONTENT_LENGTH'});

#Put the elements into an array.
@pairs = split(/&/, $buffer);

#Loop through the array and do the following:
foreach $pair (@pairs) {

#Split into $name=$value from the $pair
($name, $value) = split(/=/, $pair);

#Convert "+"'s into spaces " ".
$value =~ tr/+/ /;
$name =~ tr/+/ /;

#Convert other things like "%20" to the appropriate values.
$value =~ s/%([a-fA-F0-9][a-fA-F0-9]/pack("C", hex($1))/eg;
$name =~ s/%([a-fA-F0-9][a-fA-F0-9]/pack("C", hex($1))/eg;

#Finalize everything by putting them into a hash (%searchField).
$searchField{"$name"} = $value;
}
#############

The $searchField can be named anything you want, it doesn't matter. The:

my (%searchField, $buffer, $pair, @pairs);

is really a waist of processes unless you plan on using those names again for different variables. By taken them out, you don't have to keep passing elements between sub routines. Below is a clean code that will parse POST and GET data perfectly everytime and the the variables are set globaly so you don't have to pass them on to other subs:
<BLOCKQUOTE><font size="1" face="Verdana,Arial,Helvetica">code:</font><HR><pre>
####
sub parse_data {
####Post Data
read(STDIN, $namevalues, $ENV{'CONTENT_LENGTH'});
@namevalues = split(/&/, $namevalues);
foreach $namevalue (@namevalues) {
($name, $value) = split(/=/, $namevalue);
$name =~ tr/+/ /;
$value =~ tr/+/ /;
$name =~ s/%([a-fA-F0-9][a-fA-F0-9])/pack("C", hex($1))/eg;
$value =~ s/%([a-fA-F0-9][a-fA-F0-9])/pack("C", hex($1))/eg;
$INPUT{$name} = $value;
}
####Get Data
$temp=$ENV{'QUERY_STRING'};
@pairs=split(/&/,$temp);
foreach $item(@pairs) {
($name,$value)=split (/=/,$item,2);
$value=~tr/+/ /;
$value=~ s/%(..)/pack("c",hex($1))/ge;
$request{$name}=$value;
}
}#End Sub
[/code]

Items sent through the POST method are $INPUT{name} and GET method elements are $request{name}

Wow, that was allot, I hope it helped

July 26th, 2000, 12:13 PM