exercise: read text file line by line

c1-m4-activity/names.txt

@@ -0,0 +1,10 @@
+hoang le
+minh tran
+nghia nguyen
+tuan dang
+hung tran
+khanh tran
+tam do
+huu dao
+van ly
+nam ho

c1-m4-activity/read.go

@@ -0,0 +1,71 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"log"
+	"os"
+)
+
+const (
+	maxLength = 20
+)
+
+// Name represents data in each line from text
+type Name struct {
+	fname string
+	lname string
+}
+
+// InitMe init property for Name
+func (n *Name) InitMe(fname, lname string) {
+	n.fname = fname
+	n.lname = lname
+	var maxRunes []rune
+	if len(fname) > maxLength {
+		maxRunes = []rune(fname)
+		n.fname = string(maxRunes[:maxLength])
+	}
+	if len(lname) > maxLength {
+		maxRunes = []rune(lname)
+		n.lname = string(maxRunes[:maxLength])
+	}
+}
+
+/*
+  successively read each line
+  create a struct
+  add each struct to slice
+  iterate and print slice result
+*/
+
+func main() {
+	var fileName string
+	fmt.Println("Enter name of the file:")
+	fmt.Scan(&fileName)
+	file, err := os.Open(fileName)
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer file.Close()
+
+	names := make([]Name, 0, 5)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	scanner := bufio.NewScanner(file)
+	for scanner.Scan() {
+		text := scanner.Text()
+		for pos, char := range []byte(text) {
+			if char == ' ' {
+				names = append(names, Name{string(text[:pos]), string(text[pos+1:])})
+			}
+		}
+	}
+	if err := scanner.Err(); err != nil {
+		log.Fatal(err)
+	}
+	fmt.Printf("names value: %v\n", names)
+	fmt.Printf("length: %d,capacity: %d \n", len(names), cap(names))
+}