by Michael L. Canejo (28 Submissions)
Category: Files/File Controls/Input/Output
Difficulty: Intermediate
Date Added: Wed 3rd February 2021
Rating: 
(4 Votes)
In rare situations, there are times where you may need to know how many line-breaks a file contains "before hand". The situation for me was that I wanted to let the user of my program know what percentage of a file was being read (had to be line by line) and inorder to do this, I had to know how many lines a file contained.
Now, this is meant for HUGE lists of files. Examples are, email lists, number lists, contact lists, etc. This code will read 1,000,000 lines of a file per second (my machine is 2.6 Ghz, p4, 512MB ram). This is VERY fast. I included a benchmarking class so you can see it for yourself. I also included a zipped file which contains one million lines (16MB unzipped, 40KB zipped) and a file containing one hundred thousand lines of text as well.
NOTE: This isn't just for counting lines in a file, it can be used to count how many occurances a string comes up, such as a First Name, a Last Name, a phone number, a word, etc. The whole point of this program is to buffer a file into memory as fast as the hard drive can go (1MB buffer by default) and then read off that buffered data as it comes in.
The OLD/Popular method for counting lines:
Dim lLineCount as long, strLine as string * 1
Open "C:\file.txt" for input as #1
Do While not eof(1)
Line Input #1, strLine
lLineCount = lLineCount + 1
Loop
MsgBox lLineCount & " Lines Read."
Inputs
A file
Code Returns
how many lines or strings were found.
Download FileBuffer Count Lines, Words, Strings in Files (super fast) (14 KB)
VBcoders