英文:
Go: Reading a specific range of lines in a file
问题
我主要需要读取文件中的特定行范围，如果一个字符串与索引字符串匹配（比如说"Hello World!"），则返回true，但我不确定如何实现。我知道如何读取单独的行和整个文件，但不知道如何读取行范围。是否有任何可以帮助的库，或者有没有简单的脚本可以实现？非常感谢您的帮助！
英文:
I mainly need to read a specific range of lines in a file, and if a string is matched to an index string (let's say "Hello World!" for example) return true, but I'm not sure how to do so. I know how read individual lines and whole files, but not ranges of lines. Are there any libraries out there that can assist, or there a simple script to do it w/? Any help is greatly appreciated!
答案1
得分: 8
像这样吗？
package main
import (
"bufio"
"bytes"
"fmt"
"os"
)
func Find(fname string, from, to int, needle []byte) (bool, error) {
f, err := os.Open(fname)
if err != nil {
return false, err
}
defer f.Close()
n := 0
scanner := bufio.NewScanner(f)
for scanner.Scan() {
n++
if n < from {
continue
}
if n > to {
break
}
if bytes.Index(scanner.Bytes(), needle) >= 0 {
return true, nil
}
}
return false, scanner.Err()
}
func main() {
found, err := Find("test.file", 18, 27, []byte("Hello World"))
fmt.Println(found, err)
}
英文:
Something like this?
package main
import (
"bufio"
"bytes"
"fmt"
"os"
)
func Find(fname string, from, to int, needle []byte) (bool, error) {
f, err := os.Open(fname)
if err != nil {
return false, err
}
defer f.Close()
n := 0
scanner := bufio.NewScanner(f)
for scanner.Scan() {
n++
if n < from {
continue
}
if n > to {
break
}
if bytes.Index(scanner.Bytes(), needle) >= 0 {
return true, nil
}
}
return false, scanner.Err()
}
func main() {
found, err := Find("test.file", 18, 27, []byte("Hello World"))
fmt.Println(found, err)
}
答案2
得分: -1
如果你正在使用for循环来遍历一段行的切片，你可以使用以下类似的代码：
for _, line := range file[2:40] {
// 做一些操作
}
英文:
If you're using for to iterate through a slice of lines, you could use something along the lines of
for _,line := range file[2:40] {
// do stuff
}
通过集体智慧和协作来改善编程学习和解决问题的方式。致力于成为全球开发者共同参与的知识库，让每个人都能够通过互相帮助和分享经验来进步。
评论