Hi,

Thanks for this.

I am trying to read out the 6 characters following "DosID" in a longer string into a new variable ($dosid). Here is the code using the position. As the position is not always the same (sometimes it starts at 81, sometimes at 44, etc.), I have to use another if-clause to correct the value. This can get rather bothersome, if the position jumps around all the time. 

foreach $input (@input) {
  if (($input=~'DosID=') && ($count=~/[02468]$/)) {
   $count2++;
   $dosid=substr($input,81,6);
   if ($dosid=~'detai') {
    $dosid=substr($input,44,6);
   }
   if ($dosid=~'"') {
    chop($dosid);
   }
}

[download]
The two count variables ($count, $count2) are counting the lines of the input file and the number of lines containing the search string "DosID" respectively. I am only interested in every second occurence.

I tried it with $', but this seems to pick up the value of one of the count variables instead of the remainder of the string.

Another thing: I would like not having to specify the number of characters of the substring. Instead I would like to use a delimiter as a stop signal (in my example: a " character should delimit the substring). I could use a loop checking every character and then appending it to my variable, but I thought there might be a more elegant way of doing things.

I guess I am looking for a function like substr which includes regular expressions and if-clauses instead of fixed parameters. Thus, the start of the substring would be defined as "begin after" and the end as "stop before".

In reply to Re^2: Alternative to Substr? by New Novice
in thread Alternative to Substr? by New Novice

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