lab 1 print

8/3/2019 Lab 1 Print

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PseudocodeDefine the getFormData() function.

Initialize a buffer.

If the GET method is used, copy the form information into the buffer.

If the POST method is used, read the form information into the buffer.

Listing 20.1-20LST01.PL - The First Step is to Get the Form Information.

sub getFormData {

my($buffer) = "";

if ($ENV{'REQUEST_METHOD'} eq 'GET') {

$buffer = $ENV{'QUERY_STRING'};

}

else {

read(STDIN, $buffer, $ENV{'CONTENT_LENGTH'});

}

}

PseudocodeDeclare a hash variable to hold the form's input fields.

Call the getFormData() function.

Define the getFormData() function.

Declare a local variable to hold the reference to the input field hash.





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Iterate over the array returned by the split() function.

Decode both the input field name and value.

Create an entry in the input field hash variable.

Define the decodeURL() function.

Get the encoded string from the parameter array.

Translate all plus signs into spaces.

Convert character coded as hexadecimal digits into regular characters.

Return the decoded string.


my(%frmFlds);

getFormData(\%frmFlds);

sub getFormData {

my($hashRef) = shift;

my($buffer) = "";



}

else {


}

foreach (split(/&/, $buffer)) {


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my($key, $value) = split(/=/, $_);

$key = decodeURL($key);

$value = decodeURL($value);

%{$hashRef}->{$key} = $value;

}

}

sub decodeURL {

$_ = shift;

tr/+/ /;

s/%(..)/pack('c', hex($1))/eg;

return($_);

}

PseudocodeDeclare a hash variable to hold the form's input fields.

Call the getFormData() function.








Compress multiple

tags into one.

Convert < into < and > into > stopping HTML tags from interpretation.

Turn back on the bold and italic HTML tags.


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Remove unneded carriage returns.

Convert two newlines into a HTML paragraph tag.

Convert single newlines into spaces.








my(%frmFlds);

getFormData(\%frmFlds);

sub getFormData {


my($buffer) = "";



}

else {


}


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$value =~ s/(

\s*)+/

/g; # compress multiple

tags.

$value =~ s//>/g;

$value =~ s///ig; # turn on the bold tag.

$value =~ s!!!ig;

$value =~ s///ig; # turn on the italic tag.

$value =~ s!!!ig;

$value =~ s!\cM!!g; # Remove unneeded carriage returns.

$value =~ s!\n\n!

!g; # Convert 2 newlines into paragraph.

$value =~ s!\n! !g; # Convert newline into spaces.


}

}

sub decodeURL {

$_ = shift;

tr/+/ /;

s/%(..)/pack('c', hex($1))/eg;

return($_);

}


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PseudocodeStart the HTML web page.

Define the web page header which holds the title.

Start the body of the page.

Display a header.

Display some instructions.

Start a HTML form.

Start a HTML table.

Each row of the table is another input field.

Define the submit button.

End the table.

End the Form.

End the body of the page.

End the page.

Listing 20.4-ADDGEST.htm - The Add Entry to Guest book HTML Form

Add to our Guestbook

Add to our Guestbook

Fill in the blanks below to add to our Guestbook. The only fields that you

have to fill in are the comments and name section. Thanks!


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Your Name:

Email:

Comments:

The only thing you might need to change in order for this form to work is the ACTION modifier

in the tag. The directory where you place the CGI program might not be /cgi-bin. The

addgest.htm file will generate a web page that looks like the following figure.

Fig. 20.2 - The Add Entry Form

The CGI program in Listing 20.5 is invoked when a visitor clicks on the submit button of the

Add Entry HTML form. This program will process the form information, save it to a data fileand then create a web page to display all of the entries in the data file.

PseudocodeTurn on the warning option.

Turn on the strict pragma.


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Declare a hash variable to hold the HTML form field data.

Get the local time and pretend that it is one of the form fields.

Get the data from the form.

Save the data into a file.

Send the HTTP header to the remote web browser.

Send the start of page and header information.

Send the heading and request a horizontal line.

Call the readFormData() function to display the Guest book entries.

End the web page.








Compress multiple

tags into one.

Convert < into < and > into > stopping HTML tags from interpretation.

Turn back on the bold and italic HTML tags.

Remove unneded carriage returns.

Convert two newlines into a HTML paragraph tag.

Convert single newlines into spaces.





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Define the zeroFill() function - turns "1" into "01".

Declare a local variable to hold the number to be filled.

Declare a local variable to hold the string length that is needed.

Find difference between current string length and needed length.

If the string is big enough (like "12") then return it.

If the string is too big, prefix it with some zeroes.

Define the saveFormData() function.

Declare two local variables to hold the hash and file name.

Open the file for appending.

Store the contents of the hash in the data file.

Close the file.

Define the readFormData() function.

Declare a local variable to hold the file name.

Open the file for reading.

Iterate over the lines of the file.

Split the line into four variables using ~ as demlimiter.

Print the Guest book entry using a minimal amount of HTML tags.

Use a horizontal rule to separate entries.

Close the file.Listing 20.5-20LST05.PL - A CGI Program to Add a Guest book Entry and

Display a Guest book HTML Page

#! /user/bin/perl -w


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use strict;

my(%fields);

my($sec, $min, $hour, $mday, $mon, $year) = (localtime(time))[0..5];

my($dataFile) = "data/gestbook.dat";

$mon = zeroFill($mon, 2);

$hour = zeroFill($hour, 2);

$min = zeroFill($min, 2);

$sec = zeroFill($sec, 2);

$fields{'timestamp'} = "$mon/$mday/$year, $hour:$min:sec";

getFormData(\%fields);

saveFormData(\%fields, $dataFile);

print("Content-type: text/html\n\n");

print("\n");

print("Guestbook\n");

print("Guestbook\n");

print("\n");

readFormData($dataFile);

print("\n");

print("\n");

sub getFormData {


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my($buffer) = "";

if ($ENV{'REQUEST_METHOD'} eq "GET") {


}

else {


}





$value =~ s/(

\s*)+/

/g; # compress multiple

tags.

$value =~ s//>/g;

$value =~ s///ig; # turn on the bold tag.

$value =~ s!!!ig;

$value =~ s///ig; # turn on the italic tag.

$value =~ s!!!ig;

$value =~ s!\cM!!g; # Remove unneeded carriage returns.

$value =~ s!\n\n!

!g; # Convert 2 newlines into paragraph.

$value =~ s!\n! !g; # convert newline into space.


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}

$fields{'comments'} =~ s!\cM!!g;

$fields{'comments'} =~ s!\n\n!

!g;

$fields{'comments'} =~ s!\n!
!g;

}

sub decodeURL {

$_ = shift;

tr/+/ /;

s/%(..)/pack('c', hex($1))/eg;

return($_);

}

sub zeroFill {

my($temp) = shift;

my($len) = shift;

my($diff) = $len - length($temp);

return($temp) if $diff


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sub saveFormData {


my($file) = shift;

open(FILE, ">>$file") or die("Unable to open Guestbook data file.");

print FILE ("$hashRef->{'timestamp'}~");

print FILE ("$hashRef->{'name'}~");

print FILE ("$hashRef->{'email'}~");

print FILE ("$hashRef->{'comments'}");

print FILE ("\n");

close(FILE);

}

sub readFormData {

my($file) = shift;

open(FILE, "


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lab 1 print

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