终端输入与预期结果不符

Question

我是 Go 新手。

我写了下面的程序来让用户输入名字。

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")
}

我运行程序并输入了我的名字nixon

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

Answer 1

修改您的主要功能如下：

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

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

我添加到您的代码中的行从您的输入中删除了新行字符。

Answer 2

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

Trim 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

终端输入与预期结果不符

Terminal input doesn't match expected result

go

gofmt