Scan input from command line then TrimSuffix-CodePudding

    cin := bufio.NewReader(os.Stdin)
    fmt.Println("Enter person's name:")
    person, err := cin.ReadString('\n') 
    if err != nil {
        fmt.Println(err)
     }else{
         fmt.Print(person)
         fmt.Println(len(person))
     }
    person = strings.TrimSuffix(person,"\n") 
    fmt.Println("Enter person's quote:")
    quote, err := cin.ReadString('\n')
    if err != nil {
        fmt.Println(err)
     }else{
        fmt.Print(quote)
        fmt.Println(len(quote))
    }

    quote = strings.TrimSuffix(quote,"\n") 
    fmt.Println("------------")
    fmt.Print(person)
    fmt.Print(len(person))
    fmt.Print(quote)
    fmt.Print(len(quote))

My intention is to read a string and trim the \n trailing behind it since ReadString will include the \n. But using TrimSuffix(person,'\n') will not work and I don't understand why. Using string defined in program works but not user input. It will give strange behavior like returning an empty string and other undesired behaviors. I then checked the length of the string obtained from ReadString. E.g. user input: "abc" the length will be 5. I don't understand why. Can anyone enlightens me? I managed to achieve the intention using TrimSpace but I want to know what's wrong with this approach too.

This is what I got:

I think it's because the first 4abc got overwritten by the later one. I would expect it to be 3abc.

CodePudding user response：

If your string doesn’t contain white space, you can use fmt.Scanln, like so:

var input string
fmt.Println("Enter a string:")
fmt.Scanln(&input)

If it contains white space:

fmt.Println("Enter a string:")
scanner := bufio.NewScanner(os.Stdin)
if scanner.Scan() { // returns bool value
    input := scanner.Text()
}

CodePudding user response：

I just tried your code on Goland and I modified this line:

person = strings.TrimSuffix(person,"\n")

and I obtained this result

Enter person's name:
abc
abc
4
Enter person's quote:
abc
abc
4
------------
abc3abc3

Everything is correct here, can you explain in details what do you have as result and what do you expect?