go - 终端输入与预期结果不符

Question

我是 Go 新手。

我编写了下面的程序以允许用户输入名称。

package main

import (
    "bufio"
    "fmt"
    "os"
)

func main() {
    reader := bufio.NewReader(os.Stdin)

    fmt.Print("Enter name:")
    name, err := reader.ReadString('\n')
    if err != nil {
        panic(err)
    }

    fmt.Println(name == "nixon")
}

我运行程序并输入我的名字 nixon

为什么 fmt.Println(name == "nixon") 的输出总是 false？

Answer 1

func (*Reader) ReadString

func (b *Reader) ReadString(delim byte) (string, error)

ReadString reads until the first occurrence of delim in the input, returning a string containing the data up to and including the delimiter.

---

name 终端输入包括尾随换行符。例如，

package main

import (
    "bufio"
    "fmt"
    "os"
)

func main() {
    reader := bufio.NewReader(os.Stdin)

    fmt.Print("Enter name:")
    name, err := reader.ReadString('\n')
    if err != nil {
        panic(err)
    }
    fmt.Printf("%q\n", name)

    fmt.Println(name == "nixon")
}

输出(Linux):

Enter name:nixon
"nixon\n"
false

输出(Windows):

Enter name:nixon
"nixon\r\n"
false

---

修剪尾随换行符。例如，

package main

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

func main() {
    reader := bufio.NewReader(os.Stdin)

    fmt.Print("Enter name:")
    name, err := reader.ReadString('\n')
    if err != nil {
        panic(err)
    }
    fmt.Printf("%q\n", name)
    name = strings.TrimRight(name, "\r\n")
    fmt.Printf("%q\n", name)

    fmt.Println(name == "nixon")

输出(Linux):

Enter name:nixon
"nixon\n"
"nixon"
true

输出(Windows):

Enter name:nixon
"nixon\r\n"
"nixon"
true