in reply to Re: Write in files
in thread Write in files

The usual way to do this, is to first read the first file into a hash, basically creating a phone directory: 

open my $fh, "<", "/root/Desktop/file1.txt";
my %verzeichnis;
while (my $line = <$fh>) {
    $line =~ /RegEx/i;
    my $telefonnummer = $1;
    my $name = $2;
    $verzeichnis{lc $name} = $telefonnummer;
}
close $fh;

[download]

In a second loop (rather than a nested loop) afterwards, you would extract the name from each line, do a lookup in the hash and then write the result to a new file. At the end you can then replace your second file with the new file. 

open my $fh2, "<", "/root/Desktop/file2.txt";
open my $new, ">", "/root/Desktop/file2.new";
while (my $line2 = <$fh2>) {
    chomp $line2;
    $line2 =~ /RegEx/i;
    my $name2 = "$1,$2";
    print $new $line2;
    if( defined $verzeichnis{lc $name2} ) {
        print $new ";+49".$verzeichnis{lc $name2}; 
    }
    print $new "\n";
}
close $fh2;
close $new;

[download]

Updated a few of typos.

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Re^3: Write in files
by lolz (Initiate) on Nov 18, 2013 at 10:47 UTC
    I have a few questions to your code. what exactly does the code  $verzeichnis{lc $name} = $telefonnummer; and 
     
    if( defined $verzeichnis{lc $name2} ) {
        print $new ";+49".$verzeichnis{lc $name2}; 
    }

    [download]
    does?

    I haven't worked with  defined and  lc yet...

    Thanks for your efforts!
[reply]
[d/l]
[select]

      defined checks whether or not a key is defined in a hash, in this context it will return true if the name was found in your file 1. lc turns a string into lower case, adding a bit of robustness to the code (I assumed you wanted to do case insensitive matching).

      Generally, there is excellent documentation at http://perldoc.perl.org should you be unfamiliar with a specific function.

      UPDATE: It seems I was a bit tired when writing in this thread. While defined does the job, one really should be using exists. Apologies! A simple introduction into hashes can be found here http://www.tutorialspoint.com/perl/perl_hashes.htm but googling "perl hash" will lead to many more good hits.

[reply]
[d/l]
        what will happen if the define check will be false? The line wouldn't be written to the new file, right?

        what does the Connection from  $Verzeichnis{lc $name2}; exactly do? I want to understand all parts of the script :)
[reply]
[d/l]

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