03_input_from_the_console.go

package main

import (
	"bufio"
	"fmt"
	"os"
	"strconv"
	"strings"
)

func main() {

	//testScanf()
	//testBufioOs()
	//testBufioOsNumericValues()
}

// Scan methods are designed to get input from console, files, variables, and
// other input sources and automatically separate values from each other by
// looking for space characters
func testScanf() {
	var s string

	// Scan function is designed for analyzing and parsing the string
	// It automatically breaks up the string whenever it finds space characters

	fmt.Scanln(&s) // --> & character passes the reference of s
	fmt.Println(s)
}

// If you want simply to collect user input in a console application, you should
// instead use a couple of packages bufio and os
func testBufioOs() {

	// a reader object can collect information from a variety of inputs
	reader := bufio.NewReader(os.Stdin) // --> this means that this reader object is looking for information from standard input
	fmt.Print("Enter text: ")
	str, _ := reader.ReadString('\n') // --> the character defines when the ReadString operation needs to return
	// --> in this case, it will return whatever it reads until the new line character
	fmt.Println(str)

}

func testBufioOsNumericValues() {

	reader := bufio.NewReader(os.Stdin)
	fmt.Print("Enter a number: ")
	str, _ := reader.ReadString('\n')
	// strconv is used for converting string values to different types
	f, err := strconv.ParseFloat(strings.TrimSpace(str), 64) // 64 indicates the bitsize of the float number going to be returned
	// TrimSpace will remove the leading or trailing spaces from the string
	if err != nil {
		fmt.Println(err)
	} else {
		fmt.Println("Value of number:", f)
	}
}