我无法将html表的内容保存到文本文件中。 使用CGI和PERL

Question

Hello my friends I am fairly new in javascript and html as well so this project is taking much longer than I probably need. Here is the problem, I want to save the contents of a table into a text file.

Here is the code in the form

print start_form(-action=>"",-onSubmit=>"return false;");
print table({-border=>1,-cellpadding=>3,-name=>"tabla",-id=>"tab"},
    th(["Matricula","Nombre","Apellido Paterno","Apellido           Materno","Sexo","Edad","Carrera","Email",
    "Materias","Promedio","Borrar"]));
print   submit(-label=>'Guardar',-onClick=>'salvar();',-onSubmit=>"salvar(); return false;");
print hidden(-name=>'escondido',-id=>'hid',
             -default=>['0']);
print hidden(-name=>'escondido2',-id=>'hid2',
             -default=>['nadiemeve2']);
print   end_form;

Rows are added to the table as it reads a file using javascript, so when I want to save the contents of the displayed table into a text file I do this:

if (param) {
open FT, "+>>".param('escondido2') or die "No se puede abrir el archivo";
print FT param('celda60');
close FT;
}

Here, 'celda60' is the name of a single textfield inside a field, the name is given as the cell is created. As you might notice, I am just trying to save a single cell as a test, the thing is, that it doesn't work. It doesnt save a thing. but if I do: print FT param('celda60')."TEST"; the only thing it saves in my file is TESTESTESTEST, so the problem gotta be param('celda60') In case you wonder 'salvar()' looks like this

   function salvar(){

   var table2 = document.getElementById('tab');

   var rowCount2 = table2.rows.length - 1;
   document.getElementById('hid').value=rowCount2; }

the only thing it does is to get the amount of rows so when I get the saving thing going I can save the content inside each textfield from each cell by doing a few cycles.

Any idea of what I am doing wrong here? I mean, besides lots of rudimentary stuff I guess.

Answer 1

Client side modifications of an HTML document are not automatically reflected via CGI into the state of the server-side program. You need an additional mechanism, eg AJAX.

Answer 2

You need to read a well written Perl and CGI tutorial for sometime after 1998.

I recommend Ovid's CGI Course . It's a venerable classic, but it is very well written and does not encourage bad practices.

You've got at least one place where I can run arbitrary commands using shell escapes in my CGI arguments. That is why practices like tainting user data and 3 argument open commands are standard practices and have been for many years.

General advice:

1. Make sure you are using strict and warnings .
2. Use 3 argument open with lexical handles, or just use IO::File. open my $fh, '>>', $pathtofile or die "Ouch $!";
3. You don't have to use the CGI module with Perl to do CGI. It is one convenient way to handle parameter parsing and HTML building. There are MANY options.
4. print can handle a list of arguments. There is no need to have 50 print statements in your code.
5. Add whitespace to your code. Spacing things out makes it more readable.

On the last couple points here's an example:

sub print_form {

    print 

        start_form(-action=>"", -onSubmit=>"return false;"),

        table({-border=>1,-cellpadding=>3,-name=>"tabla",-id=>"tab"},
              th([  "Matricula",        "Nombre",
                    "Apellido Paterno", "Apellido Materno",
                    "Sexo",             "Edad",
                    "Carrera",          "Email",
                    "Materias",         "Promedio",
                    "Borrar",
              ])
        ),

        submit( -label    => 'Guardar', 
                -onClick  => 'salvar();',
                -onSubmit => 'salvar(); return false;',
        ),

        hidden( -name=>'escondido',  -id=>'hid',  -default=>['0'] ),
        hidden( -name=>'escondido2', -id=>'hid2', -default=>['nadiemeve2'] ),

        end_form();
}

Although, in my code I'd make the html and pass it back. I like to keep side effects, like printing stuff out, closely grouped.

Answer 3

Maybe you are overcomplicating your question, something like this will allow you to have a user enter a list of values to a form and then save those values to a data file on the server.

use strict;
use warnings;
use CGI;
use IO::File;

my @FIELDS = qw(
        matricula        nombre
        apellido_paterno apellido_materno
        sexo             edad
        carrera          email
        materias         promedio
        borrar
);

i    f( param('gotstuff') ) {


   my $fh = IO::File->open( 'datafile.txt', '>>' );

   my @data = param( @FIELDS );

   $fh->print join ',', @data;

   # Print a thank you for your data page here.

}
else {

     # Do your other junk here, start some html, etc
     # print the form and so on.

     print_form();

     # Print the rest of your HTML here.
}

sub print_form {

    my @fields = qw(
        matricula        nombre
        apellido_paterno apellido_materno
        sexo             edad
        carrera          email
        materias         promedio
        borrar
     );
    my @headings = map {my $w = $_; $w=~/_/ /g; uc_first $w } @fields;



    print 

        start_form(-action => script_name(), -method => 'POST' ),

        table({-border=>1,-cellpadding=>3,-name=>"tabla",-id=>"tab"},
            Tr([
              th(\@headings),
              td([ map textfield($_), @fields ]),
            ]),
        ),

        submit( -label    => 'Guardar', 
                -onClick  => 'salvar();',
                -onSubmit => 'salvar(); return false;',
        ),
        hidden( 'gotstuff', 'gotstuff' ),
        end_form();
}