I know  that experienced programmers may consider  this logic too simple. But it can prove to be a stubborn nut to crack during the debugging process. That was what I initially thought, but when I started coding for it, it took 3 evenings of my spare time.

The logic splits any text into groups of desired length. The length of the group may be less, equal to but not more than the specified character length.  The main priority is that the length should only be splitted when ever a newline occurs. If a chunk of text does not contain a newline, then the text is splitted into smaller groups based on character counting.

Eg splitting this texts (data) in group of 4 should give the following result. (Result)

Data
Abcde
f
g
Hij
Klmn
Op
Qrstuv
Wxy
Z

Result
Abcd
efg
Hij
Klm
Nop
Qrst
Uvwx
yz

The logical problem is now a thing of the past, to God's glory.

I  am programming with visual studio(vb).

yeah, it worth it bro,
i once had almost the same stuff with string tokenizer and substring (indexing) java back then, it took me 7nights(9pm_4am everynight),
I see string manipulation as one of the difficult things in programming cos its always treated as a whole entity(object as in Java) in some programming languages,

I would like to know ur algorithm, i will be xpecting urs while I try to devise an algorithm to solve the logic too.

You would have benefited from Regular Expression expertise.

The problem seems quite straightforward. It is good practice to actually completely design your processes before writing a single line of code; you can do that either on paper or with a diagramming app (if you have one). You will be surprised how easy it makes your task.

I agree with beaf, This problem doesn't look that menacing, The poster overlooked the algorithm design process,

Thanks for your replies.
@prodam, maybe when i am less busy, i would modify the code and post it online.
@ordZOUGA and beaf, I dont overlook the algorithm process. I make serious drafts before embarking on any project. Though i use onenote and hand drawn sketches a lot, I dont have other diagrammatic apps. But some function dont need that planning cos you know exactly what to do. That was exactly what I thought cos this logic is just a microscopic part of a bigger project i am currently working on. The exact point I am trying to make is that I dont spend time drawing up drafts for every simple function. Just like some other programmers, i thought it was a 5min assignment. But it proved otherwise, so i gave it a better attention.

@OP Post your code; let's see if an improvement can be made.

logica:

You would have benefited from Regular Expression expertise.

Abcde
f
g
Hij
Klmn
Op
Qrstuv
Wxy
Z

Result
Abcd
efg
Hij
Klm
Nop
Qrst
Uvwx
yz
Amen to that! Just in case you're solving similar problem in the future, just have parse into the pattern (you might have to fine tune per your language):
A[b-d]+\n[e-g]+\nhig\nKlm\\nNop\nQ[r-t]+\nU[v-z]+\/nyz$