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Hi please help!! really new to perl and regexp
I need to do string (call it field) replacement on a line.
Those lines are from application logs. I need to manipulate them
They can be single replacement or multiple replacements
all "fields" is delimited by a comma. The number of
comma is fixed, but those field can be empty (see the sample
data for example). The data comes from a source data file
for each non empty field, it can be assigned with new value

my approach:
- open the file-
- read data file line by line, store old line to temp.
- break the field using comma as delimiter and store each to global variable
- replace the fields of the temp line <<<<problem >>>
so far I can get to step 3. but things get messy in step 4.

I am using $newline =~ s/$oldField/$newFieldContent/g; to do replacement
I put this into a subroutine: replaceLog($oldLine,$oldField,$newFieldContent)
I end up with a huge if - else statements but essentially
each one is doing the same thing
plus I can't replace multiple fields with the huge if-else statement.
e.g. my huge if-else statement:
if ($field1 ne '' ){
replaceLog($oldline,$FIELD1,$NEWFIELD1);
} else ( ..repeat of above. only change the last 2 arguments.. )
so I have these problems:
1. the huge if -else is horrible and any new field addition
means the code need to grow linearly with new field addition 2. it replaces 1 field as a time, cannot to replace new
contents for field1, field2, field3 this time, while
field2 next, and field3, field8, field50 the 3rd time. really inflexible.
3. when the field has hi-ascii/dbcs content.. the
replacement doesn't seem to work. instead I get all the
character codes back.
4. when the content contains \ or \\ the replacement chokes.
Following real sample data: note that it contains ~ \ or \\
also that each field is delimited by ,
and that some fields are empty denoted by ,,
you can copy & paste the below onto notepad. turn off word wrap.

230A18121606,492000,49,30170101,something here-RP6RQL,SYSTEM,,The pres
+ent default action is to 0x22block0x22 communications.,0,0,167100,0,1
+6777216,"",369033216,,497101,RAQUINO3,497300,497201,0,0,0,0,0,0,,0,16
+7151,0,3017,C:\Program Files\something here\Anywhere\awhost32.exe,{23
+0E5C08-649A-495C-A29C-DE43A460577F},,,,MSHOME,,8.6.0.80,,,,,,,,,,,,,,
+,,0,,,0,something here-RP6RQL  
230A18121627,7,3,8,something here-RP6RQL,SYSTEM,,,,,,,16777216,"New vi
+rus definition file loaded. Version: 70831p.",0,,0,,,,,0,,,,,,,,,,RAQ
+UINO3,{230E5C08-649A-495C-A29C-DE43A460577F},,,,MSHOME,,10.0.0.359,,,
+,,,,,,,,,,,,,0,,,,something here-RP6RQL  
230A18170B03,12,4,8,something here-RP6RQL,administrator,,,,,,,16777216
+,"Changed value 'HKLM\SOFTWARE\Intel\LANDesk\VirusProtect6\CurrentVer
+sion\PatternManager\LockUpdatePatternScheduling' from '1' to '0'",0,,
+0,,,,,0,,,,,,,,,,RAQUINO3,{230E5C08-649A-495C-A29C-DE43A460577F},,(IP
+)-127.0.0.1,,MSHOME,,10.0.0.359,,,,,,,,,,,,,,,,0,,,,something here-RP
+6RQL  
230A18170E10,16,3,7,something here-RP6RQL,administrator,,,,,,,16777216
+,"Manual LiveUpdate failed to download Virus Definitions.",0,,0,,,,,0
+,,,,,,,,,,RAQUINO3,{230E5C08-649A-495C-A29C-DE43A460577F},,(IP)-127.0
+.0.1,,MSHOME,,10.0.0.359,,,,,,,,,,,,,,,,0,,,,something here-RP6RQL  
230A19161A38,45,4,14,something here-RP6RQL,administrator,,,,,,,65536,"
+C:\Program Files\Common Files\something here Shared\SPBBC\SPBBCSvc.ex
+e",0,,0,301    2656    D:\\DOCUME~1\\ALLUSE~1\\APPLIC~1\\AOLDOW~1\\TR
+ITON~2.3\\setup.exe    12    2364    C:\\Program Files\\Common Files\
+\something here Shared\\SPBBC\\SPBBCSvc.exe    C:\\Program Files\\Com
+mon Files\\something here Shared\\12345\\12345.exe    0    1,,,,0,,,,
+,,,,,,,{2D7BD59B-DF46-41BB-B2AA-E893B8D41370},,(IP)-10.0.0.10,,MSHOME
+,,,,,,,,,,,,,,,,,,0,,,,something here-RP6RQL  
230A19161A38,45,4,14,something here-RP6RQL,administrator,,,,,,,65536,"
+C:\PROGRA~1\SYMANT~2\SYMANT~2\VPTray.exe",0,,0,301    2656    D:\\DOC
+UME~1\\ALLUSE~1\\APPLIC~1\\AOLDOW~1\\TRITON~2.3\\setup.exe    10    2
+388    C:\\PROGRA~1\\SYMANT~2\\SYMANT~2\\VPTray.exe    C:\\PROGRA~1\\
+SYMANT~2\\SYMANT~2\\VPTray.exe    0    1,,,,0,,,,,,,,,,,{2D7BD59B-DF4
+6-41BB-B2AA-E893B8D41370},,(IP)-10.0.0.10,,MSHOME,,,,,,,,,,,,,,,,,,0,
+,,,something here-RP6RQL  
230A1A16271E,492000,49,30170101,something here-RP6RQL,SYSTEM,,Rule 0x2
+2Implicit block rule0x22 blocked (something here-RP6RQL(10.0.0.10)0x2
+c1040).,0,0,167103,16777343,16777216,"",68158480,,497101,RAQUINO3,497
+301,497201,0,167772170,0,0,0,0,,0,167151,0,3017,N/A,{2D7BD59B-DF46-41
+BB-B2AA-E893B8D41370},,(IP)-10.0.0.10,,MSHOME,,8.6.0.80,,,,,,,,,,,,,,
+,,0,,,0,something here-RP6RQL
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In reply to how to so this string replacement elegantly by edwardt_tril

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