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Substitutions in an html file

kvn
New User

Jun 25, 2010, 11:36 AM

Post #1 of 5 (2576 views)

Substitutions in an html file	Can't Post

Hi All,

I have an html file which have lines of this sort.

.....

<li><a href="#tab3"><?=$_['Daily']?> - <?=$_['RPO Graph']?></a></li>

.....

I am in need of replacing the above lines with the following:

<li><a href="#tab3"><?=NLS('Daily')?> - <?=NLS('RPO Graph')?></a></li>
That is substitution of
<?=$_['.TEXT.']?> To
<?=NLS(.TEXT.)?>

I have used the following code, but it is not working.

Thanks and Regards,
kvn

Zhris
User

Jun 26, 2010, 12:55 AM

Post #2 of 5 (2543 views)

Re: [kvn] Substitutions in an html file [In reply to]	Can't Post

Hi,

I think you forgot to include your code. However here is an example (untested):

Code

#!/usr/bin/perl            
use strict;           
            
my $tempfile = 'tempfile.html';      
my $htmlfile = 'htmlfile.html';     
my $search = "<\?=\$_\['\.TEXT\.'\]\?>";          
my $replace = '<?=NLS(.TEXT.)?>';           
  
open (FH1, "<$tempfile") || die "Cannot Open FH1 - $tempfile - $!";           
open (FH2, ">$htmlfile") || die "Cannot Open FH2 - $htmlfile - $!";           
  
while (my $line = <FH2>) {           
	chomp $line;           
	$line =~ s/$search/$replace/g;           
	print FH1 "$line\n";           
}           
  
close (FH2);           
close (FH1);           
  
rename($tempfile, $htmlfile);

Note that special characters which are used for pattern matching must be escaped whilst searching. Or you could use /\Q$search\E/ , however I think the $ will still need to be escaped to ensure $_ isn't interpolated.

Chris

(This post was edited by Zhris on Jun 26, 2010, 12:29 PM)

kvn
New User

Jun 26, 2010, 9:59 PM

Post #3 of 5 (2488 views)

Re: [Zhris] Substitutions in an html file [In reply to]	Can't Post

Hi CHris,
I forgot to include the code. As suggested by you, I have used the following code.

#! /usr/bin/perl
$search = '<\?=\$\_\[(.*)\]\?>' ;
$replace = '<?=NLS($1)?>';
while ($line = <>)
{
if ($line =~ m/($search)/ )
{
print $line;
$line =~ s/$search/$replace/;
print $line;
}
}

In the following, i want to replace whatever .TEXT. with text grouping (.*) and replace it as substitution in the line which has the match using the following
$line =~ s/$search/$replace/;

But I am unable to replace the text with the grouping. For example, log1 is the text content
# cat log1
<li><a href="#tab3"><?=$_['Daily']?> - <?=$_['RPO Graph']?></a></li>

# perl test.pl log1
<li><a href="#tab3"><?=$_['Daily']?> - <?=$_['RPO Graph']?></a></li>
<li><a href="#tab3"><?=NLS($1)?></a></li>

Also if i have two matches in the same line like above it is not matching the next one.

Thanks and Regards,
Vivek

Zhris
User

Jun 27, 2010, 12:08 PM

Post #4 of 5 (2450 views)

Re: [kvn] Substitutions in an html file [In reply to]	Can't Post

Hey,

The $search expression isn't escaped properly (i.e. parts which shouldn't be escaped, are) and (.*) will match after the "closing" single quote '. You also shouldn't have put the $replace expression in a variable because $1 is being interpolated before searching/replacing.

I have tested our scripts, made some changes, and here is a working example:

Code

#!/usr/bin/perl             
use strict; 
 
my $search = "\Q<?=\$_['\E([^']*)\Q']?>\E";  
 
while (my $line = <DATA>) { 
	if ($line =~ m/$search/) {        
		print "$line\n";     
		$line =~ s/$search/<?=NLS($1)?>/g;     
		print "$line\n"; 
	}      
}            
   
__DATA__ 
<li><a href="#tab3"><em><?=$_['Daily']?> - <?=$_['RPO Graph']?></em></a></li>

Output:

Code

<li><a href="#tab3"><em><?=$_['Daily']?> - <?=$_['RPO Graph']?></em></a></li> 
<li><a href="#tab3"><em><?=NLS(Daily)?> - <?=NLS(RPO Graph)?></em></a></li>

Things to note:
- I have used \Q and \E to separate groups where I don't want special characters to be activated, and I have escaped the $ in $_ to stop $_ from being interpolated.
- I have no longer put "replace" in a variable because I don't want $1 to be interpolated yet. I have kept "search" in a variable otherwise the single quotes create an issue.
- Instead of using (.*) I have used ([^']*) to ensure that it only matches anything except a single quote ' (stops any matching after the single quote ').
- To ensure all occurrences are searched and replaced, I used the g switch at the end of the regular expression.

Chris

(This post was edited by Zhris on Jun 27, 2010, 1:45 PM)

kvn
New User

Jun 29, 2010, 7:48 PM

Post #5 of 5 (2331 views)

Re: [Zhris] Substitutions in an html file [In reply to]	Can't Post

Hi Chris,
I have modified the code as suggested by you. It worked as expected.
Many Thanks for your help.

Thanks and Regards,
KVN

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