包 bufio 实现缓冲 I / O. 它包装了一个 io.Reader 或 io.Writer 对象,创建了另一个对象(Reader 或 Writer),它也实现了 I/O 接口,且为文本 I / O 提供了缓冲和一些帮助。
package main
import (
"bufio"
"fmt"
"strconv"
"strings"
)
func main() {
// An artificial input source.
const input = "1234 5678 1234567901234567890"
scanner := bufio.NewScanner(strings.NewReader(input))
// Create a custom split function by wrapping the existing ScanWords function.
split := func(data []byte, atEOF bool) (advance int, token []byte, err error) {
advance, token, err = bufio.ScanWords(data, atEOF)
if err == nil && token != nil {
_, err = strconv.ParseInt(string(token), 10, 32)
}
return
}
// Set the split function for the scanning operation.
scanner.Split(split)
// Validate the input
for scanner.Scan() {
fmt.Printf("%s\n", scanner.Text())
}
if err := scanner.Err(); err != nil {
fmt.Printf("Invalid input: %s", err)
}
}