msinfo has asked for the wisdom of the Perl Monks concerning the following question:

hi monks,

i am getting below message in my web pages, which use CGI::Ajax module

No head/html tags, nowhere to insert. Returning javascript anyway

Here is skeleton of my code: 

my $pjx = new CGI::Ajax( 'exported_func' => \&perl_func);
print $pjx->build_html($cgi, \&Show_Html);

sub perl_func
{
# ajax function
}

sub Show_Html
{
# html generating code
    # first check session info
    print $session->header();
    # generate html 
print $cgi->start_html();
# remaining html code
print $cgi->end_html();
}

[download]

Now this generates, html properly and even calls Ajax function, but displays above warning message in browser, all the time.

I went through CGI::Ajax documentation, and below are the lines, which I doubt are related to problem. Arguments: The CGI object, and either a coderef, or a string containing html. Optionally, you can send in a third parameter containing information that will get passed directly to the CGI object header() call.

or is it mandatory to write Show_Html as follows only

sub Show_HTML {
    my $html = <<EOT;
  <HTML>
# html generating code
  </HTML>
EOT
    return $html;
  }

[download]

While doing debugging with Firefox, I found out that actual response body was as follows

# html generated by Show_Html
<html xmlns="http://www.w3.org/1999/xhtml" lang="en-US" xml:lang="en-U
+S">
<head>
<title></title>
</html>

# and again html generated by cgi::ajax
<html>
</html>

[download]

Replies are listed 'Best First'.
Re: CGI::Ajax No head/html tags, nowhere to insert. Returning javascript anyway.
by poj (Abbot) on Sep 01, 2013 at 16:03 UTC
    The Show_HTML sub should return the html, not print it.
    It is not mandatory to use a here-doc, you could built it up like this ; 
    sub Show_HTML {
  
  my $html = $cgi->start_html();
  $html .= $cgi->p('Enter something');
  $html .= $cgi->input( {-type=>'text', -name=>"va1",-id=>"val1", 
  onkeyup=>"exported_func( ['val1'], ['resultdiv'] );"} );
  
  $html .= $cgi->br;
  $html .= $cgi->div( {-id=>"resultdiv"} );
  $html .= $cgi->end_html();  
  return $html;
}

    [download]
    poj
[reply]
[d/l]
[select]

      Thanks poj

      The Show_HTML sub should return the html, not print it

      I learned that from you.

      The error message goes away, when I use code format shown by you. But, when conditional statement is inserted, in between, it fails. Error says - problem at if condition. When I remove if condition, all goes well. 

      my $html = $session->header();
$html .= $cgi->start_html(-charset=>'UTF-8',-style   => {'src' => 'sty
+lesheet/style.css'});
$html .= $cgi->div({-id=>'container'}, 
                    $cgi->img({src=>'images/pic.png', height=>'100px',
+ width=>'150px'}),
            
                    if ($cgi->p(($session->is_expired) || ($session->i
+s_empty)) =1)
                    {
                    $cgi->p("logged")
                    },                    
            
                    $cgi->div(

      [download]
[reply]
[d/l]

        Doctor Doctor it hurts when I do this, but it doesn't hurt when I don't do it

        Ok then :)

[reply]
        Put the conditional outside the div ; 
        my $msg = ($session->is_expired || $session->is_empty) ? 'logged':'';
$html .= $cgi->div({-id=>'container'}, 
   $cgi->img({src=>'images/pic.png', height=>'100px',width=>'150px'}),
   $cgi->p($msg),$cgi->div(

        [download]
        poj
[reply]
[d/l]

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