perl regular expression match scalar plus punctuation - regex

I have scalars (columns in a table) that have one or two email addresses separated by a comma. such as 'Joek#xyznco.com, jrancher#candyco.us' or 'jsmith#wellingent.com,mjones#wellingent.com' for several of these records I need to remove a bad/old email address and the trailing comma (if one exists).
if jmsith#wellingent is no longer valid how do I remove that address and the trailing comma?
This only removes the address but leaves the comma.
my $general_email = 'jsmith#wellingent.com,mjones#wellingent.com';
my $bad_addr = 'jsmith#wellingent.com';
$general_email =~ s/$bad_addr//;
Thanks for any help.


You may be better off without a regex but with list splitting:
use strict;
use warnings;
sub remove_bad {
my ($full, $bad) = #_;
my #emails = split /\s*,\s*/, $full; # split at comma, allowing for spaces around the comma
my #filtered = grep { $_ ne $bad } #emails;
return join ",", #filtered;
}
print 'First: ' , remove_bad('me#example.org, you#example.org', 'me#example.org'), "\n";
print 'Last: ', remove_bad('me#example.org, you#example.org', 'you#example.org'), "\n";
print 'Middle: ', remove_bad('me#example.org, you#example.org, other#eample.org', 'you#example.org'), "\n";
First, split the bad email address list at the comma, creating an array. Filter that using grep to remove the bad address. join the remaining elements back into a string.
The above code prints:
First: you#example.org
Last: me#example.org
Middle: me#example.org,other#eample.org

Related

How to remove and ID from a string

I have a string that looks like this, they are ids in a table:
1,2,3,4,5,6,7,8,9
If someone deletes something from the database, I will need to update the string. I know that doing this it will remove the value, but not the commas. Any idea how can I check if the id has a comma before and after so my string doesn't break?
$new_values = $original_values[0];
$new_values =~ s/$car_id//;
Result: 1,2,,4,5,6,7,8,9 using the above sample (bad). It should be 1,2,4,5,6,7,8,9.

To remove the $car_id from the string:
my $car_id = 3;
my $new_values = q{1,2,3,4,5,6,7,8,9};
$new_values = join q{,}, grep { $_ != $car_id }
split /,/, $new_values;
say $new_values;
# Prints:
# 1,2,4,5,6,7,8,9
If you already removed the id(s), and you need to remove the extra commas, reformat the string like so:
my $new_values = q{,,1,2,,4,5,6,7,8,9,,,};
$new_values = join q{,}, grep { /\d/ } split /,/, $new_values;
say $new_values;
# Prints:
# 1,2,4,5,6,7,8,9

You can use
s/^$car_id,|,$car_id\b//
Details
^ - start of string
$car_id - variable value
, - comma
| - or
, - comma
$car_id - variable value
\b - word boundary.

s/^\Q$car_id\E,|,\Q$car_id\E\b//
Another approach is to store an extra leading and trailing comma (,1,2,3,4,5,6,7,8,9,)
The main benefit is that it makes it easier to search for the id using SQL (since you can search for ,$car_id,). Same goes for editing it.
On the Perl side, you'd use
s/,\K\Q$car_id\E,// # To remove
substr($_, 1, -1) # To get actual string

Ugly way: use regex to remove the value, then simplify
$new_values = $oringa_value[0];
$new_values =~ s/$car_id//;
$new_values =~ s/,+/,/;
Nice way: split and merge
$new_values = $oringa_value[0];
my #values = split(/,/, $new_values);
my $index = 0;
$index++ until $values[$index] eq $car_id;
splice(#values, $index, 1);
$new_values = join(',', #values);

Comparing filenames and determine their incremental digits

Imagine i have a sequence of files, e.g.:
...
segment8_400_av.ts
segment9_400_av.ts
segment10_400_av.ts
segment11_400_av.ts
segment12_400_av.ts
...
When the filenames are known, i can match against the filenames with a regular expression like:
/segment(\d+)_400_av\.ts/
Because i know the incremental pattern.
But what would be a generic approach to this? I mean how can i take two file names out of the list, compare them and find out where in the file name the counting part is, taking into account any other digits that can occur in the filename (the 400 in this case)?
Goal: What i want to do is to run the script against various file sequences to check for example for missing files, so this should be the first step to find out the numbering scheme. File sequences can occur in many different fashions, e.g.:
test_1.jpg (simple counting suffix)
test_2.jpg
...
or
segment9_400_av.ts (counting part inbetween, with other static digits)
segment10_400_av.ts
...
or
01_trees_00008.dpx (padded with zeros)
01_trees_00009.dpx
01_trees_00010.dpx
Edit 2: Probably my problem can be described more simple: With a given set of files, i want to:
Find out, if they are a numbered sequence of files, with the rules below
Get the first file number, get the last file number and file count
Detect missing files (gaps in the sequence)
Rules:
As melpomene summarized in his answer, the file names only differ in one substring, which consists only of digits
The counting digits can occur anywhere in the filename
The digits can be padded with 0's (see example above)
I can do #2 and #3, what i am struggling with is #1 as a starting point.

You tagged this question regex, so here's a regex-based solution:
use strict;
use warnings;
my $name1 = 'segment12_400_av.ts';
my $name2 = 'segment10_400_av.ts';
if (
"$name1\0$name2" =~ m{
\A
( \D*+ (?: \d++ \D++ )* ) # prefix
( \d++ ) # numeric segment 1
( [^\0]* ) # suffix
\0 # separator
\1 # prefix
( \d++ ) # numeric segment 2
\3 # suffix
\z
}xa
) {
print <<_EOT_;
Result of comparing "$name1" and "$name2"
Common prefix: $1
Common suffix: $3
Varying numeric parts: $2 / $4
Position of varying numeric part: $-[2]
_EOT_
}
Output:
Result of comparing "segment12_400_av.ts" and "segment10_400_av.ts"
Common prefix: segment
Common suffix: _400_av.ts
Varying numeric parts: 12 / 10
Position of varying numeric part: 7
It assumes that
the strings are different (guard the condition with $name1 ne $name2 && ... if that's not guaranteed)
there's only one substring that's different between the input strings (otherwise it won't find any match)
the differing substring consists of digits only
all digits surrounding the first point of difference are part of the varying increment (e.g. the example above recognizes segment as the common prefix, not segment1)
The idea is to combine the two names into a single string (separated by NUL, which is unambiguous because filenames can't contain \0), then let the regex engine do the hard work of finding the longest common prefix (using greediness and backtracking).
Because we're in a regex, we can get a bit more fancy than just finding the longest common prefix: We can make sure that the prefix doesn't end with a digit (see the segment1 vs. segment case above) and we can verify that the suffix is also the same.

See if this works for you:
use strict;
use warnings;
sub compare {
my ( $f1, $f2 ) = #_;
my #f1 = split /(\d+)/sxm, $f1;
my #f2 = split /(\d+)/sxm, $f2;
my $i = 0;
my $out1 = q{};
my $out2 = q{};
foreach my $p (#f1) {
if ( $p eq $f2[$i] ) {
$out1 .= $p;
$out2 .= $p;
}
else {
$out1 .= sprintf ' ((%s)) ', $p;
$out2 .= sprintf ' ((%s)) ', $f2[$i];
}
$i++;
}
print $out1 . "\n";
print $out2 . "\n";
return;
}
print "Test1:\n";
compare( 'segment8_400_av.ts', 'segment9_400_av.ts' );
print "\n\nTest2:\n";
compare( 'segment999_8_400_av.ts', 'segment999_9_400_av.ts' );
You basically split strings by starting/ending digits, the loop through the items and compare each of the 'pieces'. If they are equal, you accumulate. If not, then you highlight the differences and accumulate.
Output (I'm using ((number)) for the highlight)
Test1:
segment ((8)) _400_av.ts
segment ((9)) _400_av.ts
Test2:
segment999_ ((8)) _400_av.ts
segment999_ ((9)) _400_av.ts

I assume that only the counter differs across the strings
use warnings;
use strict;
use feature 'say';
my ($fn1, $fn2) = ('segment8_400_av.ts', 'segment12_400_av.ts');
# Collect all numbers from all strings
my #nums = map { [ /([0-9]+)/g ] } ($fn1, $fn2);
my ($n, $pos); # which number in the string, at what position
# Find which differ
NUMS:
for my $j (1..$#nums) { # strings
for my $i (0..$#{$nums[0]}) { # numbers in a string
if ($nums[$j]->[$i] != $nums[0]->[$i]) { # it is i-th number
$n = $i;
$fn1 =~ /($nums[0]->[$i])/g; # to find position
$pos = $-[$i];
say "It is $i-th number in a string. Position: $pos";
last NUMS;
}
}
}
We loop over the array with arrayrefs of numbers found in each string, and over elements of each arrayref (eg [8, 400]). Each number in a string (0th or 1st or ...) is compared to its counterpart in the 0-th string (array element); all other numbers are the same.
The number of interest is the one that differs and we record which number in a string it is ($n-th).
Then its position in the string is found by matching it again and using #- regex variable with (the just established) index $n, so the offset of the start of the n-th match. This part may be unneeded; while question edits helped I am still unsure whether the position may or not be useful.
Prints, with position counting from 0
It is 0-th number in a string. Position: 7
Note that, once it is found that it is the $i-th number, we can't use index to find its position; an number earlier in strings may happen to be the same as the $i-th one, in this string.
To test, modify input strings by adding the same number to each, before the one of interest.
Per question update, to examine the sequence (for missing files for instance), with the above findings you can collect counters for all strings in an array with hashrefs (num => filename)
use Data::Dump qw(dd);
my #seq = map { { $num[$_]->[$n] => $fnames[$_] } } 0..$#fnames;
dd \#seq;
where #fnames contains filenames (like two picked for the example above, $fn1 and $fn2). This assumes that the file list was sorted to begin with, or add the sort if it wasn't
my #seq =
sort { (keys %$a)[0] <=> (keys %$b)[0] }
map { { $num[$_]->[$n] => $fnames[$_] } }
0..$#fnames;
The order is maintained by array.
Adding this to the above example (with two strings) adds to the print
[
{ 8 => "segment8_400_av.ts" },
{ 12 => "segment12_400_av.ts" },
]
With this all goals in "Edit 2" should be straighforward.

I suggest that you build a regex pattern by changing all digit sequences to (\d+) and then see which captured values have changed
For instance, with segment8_400_av.ts and
segment9_400_av.ts you would generate a pattern /segment(\d+)_(\d+)_av\.ts/. Note that s/\d+/(\d+)/g will return the number of numeric fields, which you will need for the subsequent check
The first would capture 8 and 400 which the second would capture 9 and 400. 8 is different from 9, so it is in that region of the string where the number varies
I can't really write much code as you don't say what sort of result you want from this process

regular expression help: catch this: |TrxId=475665|

For example I have a string:
MsgNam=WMS.WEATXT|VersionsNr=0|TrxId=475665|MndNr=0257|Werk=0000|WeaNr=0171581054|WepNr=|WeaTxtTyp=110|SpraNam=ru|WeaTxtNr=2|WeaTxtTxt=100 111|
and I want to catch this: |TrxId=475665|
after TrxId= it could be any numbers and any amount of them, so regex should catch as well:
|TrxId=111333| and |TrxId=0000011112222| and |TrxId=123|

TrxId=(\d+)
That would give a group (1) with the TrxId.
PS: Use global modifier.

The regex should look somewhat like this:
TrxId=[0-9]+
It will match TrxId= followed by at least one digit.

An example solution in Python:
In [107]: data = 'MsgNam=WMS.WEATXT|VersionsNr=0|TrxId=475665|MndNr=0257|Werk=0000|WeaNr=0171581054|WepNr=|WeaTxtTyp=110|SpraNam=ru|WeaTxtNr=2|WeaTxtTxt=100 111|'
In [108]: m = re.search(r'\|TrxId=(\d+)\|', data)
In [109]: m.group(0)
Out[109]: '|TrxId=475665|'
In [110]: m.group(1)
Out[110]: '475665'

/MsgNam\=.*?\|(TrxId\=\d+)\|.*/
for example in perl:
$a = "MsgNam=WMS.WEATXT|VersionsNr=0|TrxId=475665|MndNr=0257|Werk=0000|WeaNr=0171581054|WepNr=|WeaTxtTyp=110|SpraNam=ru|WeaTxtNr=2|WeaTxtTxt=100111|";
$a =~ /MsgNam\=.*?\|(TrxId\=\d+)\|.*/;
print $1;
will print TrxId=475665

You know what your delimiters look like, so you don't need a regex, you need to split. Here's an implementation in Perl.
use strict;
use warnings;
my $input = "MsgNam=WMS.WEATXT|VersionsNr=0|TrxId=475665|MndNr=0257|Werk=0000|WeaNr=0171581054|WepNr=|WeaTxtTyp=110|SpraNam=ru|WeaTxtNr=2|WeaTxtTxt=100 111|";
my #first_array = split(/\|/,$input); #splitting $input on "|"
#Now, since the last character of $input is "|", the last element
#of this array is undef (ie the Perl equivalent of null)
#So, filter that out.
#first_array = grep{defined}#first_array;
#Also filter out elements that do not have an equals sign appearing.
#first_array = grep{/=/}#first_array;
#Now, put these elements into an associative array:
my %assoc_array;
foreach(#first_array)
{
if(/^([^=]+)=(.+)$/)
{
$assoc_array{$1} = $2;
}
else
{
#Something weird may be happening...
#we may have an element starting with "=" for example.
#Do what you want: throw a warning, die, silently move on, etc.
}
}
if(exists $assoc_array{TrxId})
{
print "|TrxId=" . $assoc_array{TrxId} . "|\n";
}
else
{
print "Sorry, TrxId not found!\n";
}
The code above yields the expected output:
|TrxId=475665|
Now, obviously this is more complex than some of the other answers, but it's also a bit more robust in that it allows you to search for more keys as well.
This approach does have a potential issue if your keys appear more than once. In that case, it's easy enough to modify the code above to collect an array reference of values for each key.

I want to replace ',' on the 150th location in a String with a <br>

My String is : PI Last Name equal to one of
('AARONSON','ABDEL MEGUID','ABDEL-LATIF','ABDOOL KARIM','ABELL','ABRAMS','ACKERMAN','ADAIR','ADAMS','ADAMS-CAMPBELL', 'ADASHI','ADEBAMOWO','ADHIKARI','ADIMORA','ADRIAN', 'ADZERIKHO','AGADJANYAN','AGARWAL','AGOT', 'AGUIRRE-CRUZ','AHMAD','AHMED','AIKEN', 'AINAMO', 'AISENBERG','AJAIYEOBA','AKA','AKHTAR','AKINGBEMI','AKINYINKA','AKKERMAN','AKSOY','AKYUREK', 'ALBEROLA-ILA','ALBERT','ALCANTARA' ,'ALCOCK','ALEMAN', 'ALEXANDER','ALEXANDRE','ALEXANDROV','ALEXANIAN','ALLAND','ALLEN','ALLISON','ALPER', 'ALTMAN','ALVAREZ','AMARYAN','AMBESI-IMPIOMBATO','AMEGBETO','AMOWITZ', 'ANAGNOSTARAS','ANAND','ANDERSEN','ANDERSON', 'ANDRADE','ANDREEFF','ANDROPHY','ANGER','ANHOLT','ANTHONY','ANTLE','ANTONELLI','ANTONY', 'ANZULOVICH', 'APODACA','APOSHIAN','APPEL','APPLEBY','APRIL','ARAUJO','ARBIB','ARBOLEDA', 'ARCHAKOV','ARCHER', 'ARECHAVALETA-VELASCO','ARENS','ARGON','ARGYROKASTRITIS', 'ARIAS','ARIZAGA','ARMSTRONG','ARNON', 'ARSHAVSKY','ARVIN','ASATRYAN','ASCOLI','ASKENASE','ASSI','ATALAY','ATANASOVA','ATKINSON','ATTYGALLE','ATWEH','AU','AVETISYAN','AWE','AYOUB','AZAD','BACSO','BAGASRA','BAKER','BALAS', 'BALCAZAR','BALK','BALKAY','BALLOU','BALRAJ','BALSTER','BANERJEE','BANKOLE','BANTA','BARAL','BARANOWSKA','BARBAS', 'BARBER','BARILLAS-MURY','BARKHOLT','BARNES','BARNETT','BARRETT','BARRIA','BARROW','BARROWS','BARTKE','BARTLETT','BASSINGTHWAIGHTE','BASSIOUNY','BASU','BATES','BATTAGLIA','BATTERMAN','BAUER','BAUERLE','BAUM','BAUME', 'BAUMLER','BAVISTER','BAWA','BAYNE','BEASLEY','BEATTY','BEATY','BEBENEK','BECK','BECKER','BECKMAN','BECKMAN-SUURKULA' ,'BEDFORD','BEDOLLA','BEEBE','BEEMON','BEHETS','BEHRMAN','BEIER','BEKKER','BELL','BELLIDO','BELMAIN', 'BENATAR','BENBENISHTY','BENBROOK','BENDER','BENEDETTI','BENNETT','BENNISH','BENZ','BERG','BERGER','BERGEY','BERGGREN','BERK','BERKOWITZ','BERLIN','BERLINER','BERMAN','BERTINO','BERTOZZI','BERTRAND','BERWICK','BETHONY','BEYERS','BEYRER' ,'BEZPROZVANNY','BHAGWAT','BHANDARI','BHARGAVA','BHARUCHA','BHUJWALLA','BIANCO','BIDLACK','BIELERT','BIER','BIESSMANN','BIGELOW' ,'BILLER','BILLINGS','BINDER','BINDMAN','BINUTU','BIRBECK','BIRGE','BIRNBAUM','BIRO','BIRT','BISHAI','BISHOP','BISSELL','BJORKEGREN','BJORNSTAD','BLACK','BLANCHARD','BLASS','BLATTNER','BLIGNAUT','BLOCH','BLOCK','BLOOM','BLOOM,','BLUM','BLUMBERG' ,'BLUMENTHAL','BLYUKHER','BODDULURI','BOFFETTA','BOGOLIUBOVA', 'BOLLINGER','BOLLS','BOMSZTYK','BONANNO','BONNER','BOOM','BOOTHROYD','BOPPANA','BORAWSKI','BORG','BORIS-LAWRIE','BORISY','BORLONGAN','BORNSTEIN','BORODOVSKY','BORST','BOS','BOTO','BOWDEN','BOWEN','BOYCE-JACINO','BRADEN','BRADY' ,'BRAITHWAITE','BRANN','BRASH','BRAUNSTEIN', 'BREMAN','BRENNAN','BRENNER','BRETSCHER','BREW','BREYSSE','BRIGGS','BRITES','BRITT','BRITTENHAM','BRODIE','BRODY','BROOK','BROOTEN','BROSCO','BROSNAN','BROWN','BROWNE','BRUCKNER','BRUNENGRABER','BRYL','BRYSON','BU','BUCHAN','BUDD','BUDNIK', 'BUEKENS','BUKRINSKY','BULLMORE','BULUN','BURBANO','BURGENER','BURGESS','BURKS','BURMEISTER','BURNETT','BURNHAM','BURNS','BURRIDGE','BURTON','BUSCIGLIO','BUSHEK','BUSIJA','BUZSAKI','BZYMEK','CABA')
I need to have a regex which will greedily looks for up to 150 characters with a last character being a ','. And then replace the last ',' of the 150 with a <br />
Any suggestions pls?
I used this ','(?=[^()]*\)) but this one replaces all the occurences. I want the 150th ones to be replaced.
Thanks everyone for your suggestions. I managed to do it with Java code instead of regex.
StringBuilder sb = new StringBuilder(html);
int i = 0;
while ((i = sb.indexOf("','", i + 150)) != -1) {
int j = sb.lastIndexOf("','", i + 150);
sb.insert(i+1, "<BR>");
}
return sb.toString();
However, this breaks at the first encounter of ',' in the 150 chars.
Can anyone help modify my code to incorporate the break at the last occurence of ',' withing the 150 chars.

You'll want something like this:
Look for every occurrence of \([^)]+*,[^)]+*\) (Find a parenthesis-wrapped string with a comma in it and then run the following regular expression on each of the matched elements:
(.{135,150}[^,]*?),
The first number is the minimum number of characters you want to match before you add a break tag -- the second is the maximum number of characters you would like to match before inserting a break tag. If there is no , between the characters in question then the regular expression will continue to consume characters until it finds a comma.

You could probably do it like this:
regex ~ /(^.{1,14}),/
replacement ~ '\1<replacement' or "$1<insert your text>"
In Perl:
$target = ','x 22;
$target =~ s/(^ .{1,14}) , /$1<15th comma>/x;
print $target;
Output
,,,,,,,,,,,,,,<15th comma>,,,,,,,
Edit: As an alternative, if you want to break the string up into succesive 150 or less
you could do it this way:
regex ~ /(.{1,150},)/sg
replacement ~ '\1<br/>' or "$1<br\/>"
// That is a regex of type global (/g) and include newlines (/s)
In Perl:
$target = "
('AARONSON','ABDEL MEGUID','ABDEL-LATIF','ABDOOL KARIM','ABELL','ABRAMS','ACKERMAN','ADAIR','ADAMS','ADAMS-CAMPBELL', 'ADASHI','ADEBAMOWO','ADHIKARI','ADIMORA','ADRIAN', 'ADZERIKHO','AGADJANYAN','AGARWAL','AGOT', 'AGUIRRE-CRUZ','AHMAD','AHMED','AIKEN', 'AINAMO', 'AISENBERG','AJAIYEOBA','AKA','AKHTAR','AKINGBEMI','AKINYINKA','AKKERMAN','AKSOY','AKYUREK', 'ALBEROLA-ILA','ALBERT','ALCANTARA' ,'ALCOCK','ALEMAN', 'ALEXANDER','ALEXANDRE','ALEXANDROV','ALEXANIAN','ALLAND','ALLEN','ALLISON','ALPER', 'ALTMAN', ... )
";
if ($target =~ s/( .{1,150} , )/$1<br\/>/sxg) {
print $target;
}
Output:
('AARONSON','ABDEL MEGUID','ABDEL-LATIF','ABDOOL KARIM','ABELL','ABRAMS','ACKERMAN','ADAIR','ADAMS','ADAMS-CAMPBELL', 'ADASHI','ADEBAMOWO','ADHIKARI',<br/>'ADIMORA','ADRIAN', 'ADZERIKHO','AGADJANYAN','AGARWAL','AGOT', 'AGUIRRE-CRUZ','AHMAD','AHMED','AIKEN', 'AINAMO', 'AISENBERG','AJAIYEOBA','AKA',<br/>'AKHTAR','AKINGBEMI','AKINYINKA','AKKERMAN','AKSOY','AKYUREK', 'ALBEROLA-ILA','ALBERT','ALCANTARA' ,'ALCOCK','ALEMAN', 'ALEXANDER','ALEXANDRE',<br/>'ALEXANDROV','ALEXANIAN','ALLAND','ALLEN','ALLISON','ALPER', 'ALTMAN',<br/> ... )

Remove a number from a comma separated string while properly removing commas

FOR EXAMPLE: Given a string... "1,2,3,4"
I need to be able to remove a given number and the comma after/before depending on if the match is at the end of the string or not.
remove(2) = "1,3,4"
remove(4) = "1,2,3"
Also, I'm using javascript.

As jtdubs shows, an easy way is is to use a split function to obtain an array of elements without the commas, remove the required element from the array, and then rebuild the string with a join function.
For javascript something like this might work:
function remove(array,to_remove)
{
var elements=array.split(",");
var remove_index=elements.indexOf(to_remove);
elements.splice(remove_index,1);
var result=elements.join(",");
return result;
}
var string="1,2,3,4,5";
var newstring = remove(string,"4"); // newstring will contain "1,2,3,5"
document.write(newstring+"<br>");
newstring = remove(string,"5");
document.write(newstring+"<br>"); // will contain "1,2,3,4"
You also need to consider the behavior you want if you have repeats, say the string is "1,2,2,4" and I say "remove(2)" should it remove both instances or just the first? this function will remove only the first instance.

Just use multiple substitutions.
s/^$removed,//;
s/,$removed$//;
s/,$removed,/,/;
This will be easier than trying to invent a single replacement that handles all those cases.

string input = "1,2,3,4";
List<string> parts = new List<string>(input.Split(new char[] { ',' }));
parts.RemoveAt(2);
string output = String.Join(",", parts);

Instead of using regex, I would do something like:
- split on comma
- delete the right element
- join with comma
Here is a perl script that does the job:
#!/usr/bin/perl
use 5.10.1;
use strict;
use warnings;
my $toremove = 5;
my $string = "1,2,3,4,5";
my #tmp = split/,/, $string;
#tmp = grep{ $_ != $toremove }#tmp;
$string =join',', #tmp;
say $string;
Output:
1,2,3,4

Javascript has improved since this question was posted.
I use the following regex to remove items from a csv string
let searchStr = "359";
let regex = new RegExp("^" + searchStr + ",?|," + searchStr);
csvStr = csvStr.replace(regex, "");
If the child_id is the start, middle or end, or only item it is replaced.
If the searchStr is at the start of the csvStr it and any trailing comma is replaced. Else if the searchStr is anywhere else in the csvStr it must be preceded with a comma so the searchStr and its preceding comma are replaced by an empty string.