使用Go语言(golang)写个简单的爬虫

package main
import (
	"fmt"
	"io/ioutil"
	"net/http"
	"regexp"
)
var (
	ptnIndexItem = regexp.MustCompile(`<a target="_blank" href="(.+\.html)" title=".+" >(.+)</a>`)
	ptnContentRough = regexp.MustCompile(`(?s).*<div class="artcontent">(.*)<div id="zhanwei">.*`)
	ptnBrTag = regexp.MustCompile(`<br>`)
	ptnHTMLTag = regexp.MustCompile(`(?s)</?.*?>`)
	ptnSpace = regexp.MustCompile(`(^\s+)|( )`)
)
func Get(url string) (content string, statusCode int) {
	resp, err1 := http.Get(url)
	if err1 != nil {
		statusCode = -100
		return
	}
	defer resp.Body.Close()
	data, err2 := ioutil.ReadAll(resp.Body)
	if err2 != nil {
		statusCode = -200
		return
	}
	statusCode = resp.StatusCode
	content = string(data)
	return
}
type IndexItem struct {
	url string
	title string
}
func findIndex(content string) (index []IndexItem, err error) {
	matches := ptnIndexItem.FindAllStringSubmatch(content, 10000)
	index = make([]IndexItem, len(matches))
	for i, item := range matches {
		index[i] = IndexItem{"http://www.yifan100.com" + item[1], item[2]}
	}
	return
}
func readContent(url string) (content string) {
	raw, statusCode := Get(url)
	if statusCode != 200 {
		fmt.Print("Fail to get the raw data from", url, "\n")
		return
	}
	match := ptnContentRough.FindStringSubmatch(raw)
	if match != nil {
		content = match[1]
	} else {
		return
	}
	content = ptnBrTag.ReplaceAllString(content, "\r\n")
	content = ptnHTMLTag.ReplaceAllString(content, "")
	content = ptnSpace.ReplaceAllString(content, "")
	return
}
func main() {
	fmt.Println(`Get index ...`)
	s, statusCode := Get("http://www.yifan100.com/dir/15136/")
	if statusCode != 200 {
		return
	}
	index, _ := findIndex(s)
	fmt.Println(`Get contents and write to file ...`)
	for _, item := range index {
		fmt.Printf("Get content %s from %s and write to file.\n", item.title, item.url)
		fileName := fmt.Sprintf("%s.txt", item.title)
		content := readContent(item.url)
		ioutil.WriteFile(fileName, []byte(content), 0644)
		fmt.Printf("Finish writing to %s.\n", fileName)
	}
}

有疑问加站长微信联系(非本文作者)

• 请尽量让自己的回复能够对别人有帮助
• 支持 Markdown 格式, **粗体**、~~删除线~~、`单行代码`
• 支持 @ 本站用户;支持表情(输入 : 提示),见 Emoji cheat sheet
• 图片支持拖拽、截图粘贴等方式上传