Insert string at line number nodejs

Question

I have a file that I would like to modify. Is there a way to insert a string to a file at a specific line number? with NodeJS

I really thank you for helping me out<

Answer 1

If you are on a Unix system then you probably want to use sed, like so to add some text to the middle of the file:

#!/bin/sh
text="Text to add"
file=data.txt

lines=`wc -l $file | awk '{print $1}'`

middle=`expr $lines / 2`

# If the file has an odd number of lines this script adds the text
# after the middle line. Comment this block out to add before
if [ `expr $lines % 2` -eq 1 ]
then
  middle=`expr $middle + 1`
fi

sed -e "${middle}a $text" $file

Note: above example is from here.

With NodeJS it appears that there are some npm packages that might help, like sed.js, or replace.