cómo leer un archivo línea por línea en el ejemplo de código golang

Ya no necesitas investigar más por internet ya que has llegado al espacio necesario, poseemos la respuesta que buscas pero sin complicarte.

Ejemplo 1: golang lee el archivo línea por línea

package main

import("bufio""bytes""fmt""io""os")funcreadFileWithReadString(fn string)(err error)
    fmt.Println("readFileWithReadString")

    file, err := os.Open(fn)defer file.Close()if err !=nilreturn err
    // Start reading from the file with a reader.
    reader := bufio.NewReader(file)var line stringfor
        line, err = reader.ReadString('n')

        fmt.Printf(" > Read %d charactersn",len(line))// Process the line here.
        fmt.Println(" > > "+limitLength(line,50))if err !=nilbreakif err != io.EOF 
        fmt.Printf(" > Failed!: %vn", err)returnfuncreadFileWithScanner(fn string)(err error)
    fmt.Println("readFileWithScanner - this will fail!")// Don't use this, it doesn't work with long lines...

    file, err := os.Open(fn)defer file.Close()if err !=nilreturn err
    // Start reading from the file using a scanner.
    scanner := bufio.NewScanner(file)for scanner.Scan()
        line := scanner.Text()

        fmt.Printf(" > Read %d charactersn",len(line))// Process the line here.
        fmt.Println(" > > "+limitLength(line,50))if scanner.Err()!=nil
        fmt.Printf(" > Failed!: %vn", scanner.Err())returnfuncreadFileWithReadLine(fn string)(err error)
    fmt.Println("readFileWithReadLine")

    file, err := os.Open(fn)defer file.Close()if err !=nilreturn err
    // Start reading from the file with a reader.
    reader := bufio.NewReader(file)forvar buffer bytes.Buffer

        var l []bytevar isPrefix boolfor
            l, isPrefix, err = reader.ReadLine()
            buffer.Write(l)// If we've reached the end of the line, stop reading.if!isPrefix break// If we're just at the EOF, breakif err !=nilbreakif err == io.EOF break

        line := buffer.String()

        fmt.Printf(" > Read %d charactersn",len(line))// Process the line here.
        fmt.Println(" > > "+limitLength(line,50))if err != io.EOF 
        fmt.Printf(" > Failed!: %vn", err)returnfuncmain()testLongLines()testLinesThatDoNotFinishWithALinebreak()functestLongLines()
    fmt.Println("Long lines")
    fmt.Println()createFileWithLongLine("longline.txt")readFileWithReadString("longline.txt")
    fmt.Println()readFileWithScanner("longline.txt")
    fmt.Println()readFileWithReadLine("longline.txt")
    fmt.Println()functestLinesThatDoNotFinishWithALinebreak()
    fmt.Println("No linebreak")
    fmt.Println()createFileThatDoesNotEndWithALineBreak("nolinebreak.txt")readFileWithReadString("nolinebreak.txt")
    fmt.Println()readFileWithScanner("nolinebreak.txt")
    fmt.Println()readFileWithReadLine("nolinebreak.txt")
    fmt.Println()funccreateFileThatDoesNotEndWithALineBreak(fn string)(err error)
    file, err := os.Create(fn)defer file.Close()if err !=nilreturn err
    

    w := bufio.NewWriter(file)
    w.WriteString("Does not end with linebreak.")
    w.Flush()returnfunccreateFileWithLongLine(fn string)(err error)
    file, err := os.Create(fn)defer file.Close()if err !=nilreturn err
    

    w := bufio.NewWriter(file)

    fs :=1024*1024*4// 4MB// Create a 4MB long line consisting of the letter a.for i :=0; i < fs; i++
        w.WriteRune('a')// Terminate the line with a break.
    w.WriteRune('n')// Put in a second line, which doesn't have a linebreak.
    w.WriteString("Second line.")

    w.Flush()returnfunclimitLength(s string, length int)stringiflen(s)< length return s
    return s[:length]

Ejemplo 2: línea de lectura de golang

package main

import"fmt"funcmain()
	x :=string
	fmt.Scanln(&x)

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