Golang : Read a file into an array or slice example

Ok, got a junior developer that wants to know how to read a text file content line by line into an array or slice. He is dealing with a legacy software that doesn't send out data either in JSON or XML format. The legacy software output is in text format.

Solution :

Use strings.Split() function with newline (\n) as the separator and ioutil.ReadFile() function.

Here you go!

 package main

 import (

 func main() {
  if len(os.Args) <= 1 {
 fmt.Printf("USAGE : %s <target_filename> \n", os.Args[0])

  fileName := os.Args[1]

  fileBytes, err := ioutil.ReadFile(fileName)

  if err != nil {

  sliceData := strings.Split(string(fileBytes), "\n")




  See also : Golang : Display a text file line by line with line number example

By Adam Ng(黃武俊)

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