在esou.com使用任意小说的任意一章的url作为参数，获取这本小说的所有文本内容，并按照章节保存为txt （貌似已经因为esou网站的更新不管用了）

gistfile1.txt

package main

import (
	"fmt"
	"io/ioutil"
	"net/http"
	"os"
	"strings"
)

func getHtmlContentWithUrl(url string) []byte {
	resp, err := http.Get(url)
	defer resp.Body.Close()
	body, err := ioutil.ReadAll(resp.Body)
	if err == nil {
		return body[:]
	} else {
		return []byte{}
	}
}

func isPathExist(path string) bool {
	_, err := os.Stat(path)
	if err == nil {
		return true
	}
	if os.IsNotExist(err) {
		return false
	}
	return false
}

func makeDir(dir string) string {
	if isPathExist(dir) == false {
		os.Mkdir(dir, 0700)
		return dir
	}
	return ""
}

func makeFileWithBytes(url string, content []byte) {
	relativePath := "./pages/"
	makeDir(relativePath)
	relativePath += url
	fmt.Println(relativePath)
	file, err := os.Create(relativePath)
	if nil == err {
		defer file.Close()
		file.Write(content)
	}
}

func hasNextPage(currentPage string) bool {
	mainTagContent := ">下章</a>"
	index := strings.Index(currentPage, mainTagContent)
	if index != -1 {
		return true
	}
	return false
}

func getPageContent(content string) (string, string) {
	title := ""
	txt := ""
	titleStart := "class=\"easou_tit2\">"
	index := strings.Index(content, titleStart)
	if -1 != index {
		subcontent := content[index+len(titleStart):]
		index = strings.Index(subcontent, "<")
		title = subcontent[:index]
		// fmt.Println(title)

		subcontent = subcontent[index:]
		contentStart := "class=\"easou_con\">"
		index = strings.Index(subcontent, contentStart)
		subcontent = subcontent[index+len(contentStart):]
		index = strings.Index(subcontent, "</div>")
		txt = subcontent[:index]
		txt = strings.Replace(txt, "<br/>", "\n", -1)
		// fmt.Println(txt)
	}
	return title, txt
}

func savePage(content string, page int) {
	title, txt := getPageContent(content)
	pageContent := title + "\n\n" + txt
	makeFileWithBytes(fmt.Sprintf("%d.html", page), []byte(pageContent))
}

func getPage(url string, page int) bool {
	bytes := getHtmlContentWithUrl(url)
	hasNext := hasNextPage(string(bytes))
	savePage(string(bytes), page)
	// makeFileWithBytes(fmt.Sprintf("%d.html", page), bytes)
	return hasNext
}

func pageUrl(page int, nid string) string {
	return fmt.Sprintf("http://book.easou.com/c/show.m?&nid=%s&st=%d", nid, page)
}

func getContent(nid string) {
	st := 1
	for {
		url := pageUrl(st, nid)
		fmt.Println(url)
		hasNext := getPage(url, st)
		if !hasNext {
			break
		}
		st++
	}
}

func getNid(url string) string {
	index := strings.Index(url, "nid=")
	if index != -1 {
		subUrl := url[index+4:]
		index = strings.Index(subUrl, "&")
		if index != -1 {
			return subUrl[:index]
		} else {
			return subUrl
		}
	}
	return ""
}

func main() {
	url := os.Args[1]
	getContent(getNid(url))
}