Golang爬虫，Go&&正则爬取数据，杠杆的

**字符** - ——匹配任意字符 e.g: abc. 结果: abcd,abcx,abc9; - [] ——匹配括号中任意一个字符 e.g: [abc]d 结果：ad,cd,1d； - - ——[-]中表示范围 e.g: [A-Za-z0-9]； - ^ ——[^]中表示除括号中的任意字符 e.g：[^xy]a 结果：aa,da,不能为xa,ya； **数量限定** - ？ ——前面单元匹配0或1次； - + ——前面单元匹配1或多次； - * ——前面单元匹配0或多次； - {,} ——显示个数上下线；e.g ： ip地址——[0-9]{1,3}.[0-9]{1,3}.[0-9]{1,3}.[0-9]{1,3}； **其他** - \ ——转义字符; - | ——条件或; - () ——组成单元 如果字符串本身有括号"[(] aaa. [)]" ; **方法** ``` //参数正则字符串，返回值*Regexp str := regexp.MustCompile(string) //参数要查找的数据，查找次数-1为全局，返回值二维数组，查找出的字符串+正则字符串 var result [][]string = str.FindAllStringSubmatch(data, -1) ``` **爬虫** 爬取xx园所有文章阅读量，评论，推荐； ```go package main import ( "fmt" "io" "net/http" "regexp" "strconv" ) var readCount int = 0 var commentCount int = 0 var diggCount int = 0 //http读取网页数据写入result返回 func HttpGet(url string) (result string, err error) { resp, err1 := http.Get(url) if err1 != nil { err = err1 return } defer resp.Body.Close() buf := make([]byte, 4096) for { n, err2 := resp.Body.Read(buf) //fmt.Println(url) if n == 0 { break } if err2 != nil && err2 != io.EOF { err = err2 return } result += string(buf[:n]) } return result, err } //横向纵向爬取文章标题数据，并累计数值 func SpiderPageDB(index int, page chan int) { url := "https://www.cnblogs.com/littleperilla/default.html?page=" + strconv.Itoa(index) result, err := HttpGet(url) if err != nil { fmt.Println("HttpGet err:", err) return } str := regexp.MustCompile("post-view-count\">阅读[(](?s:(.*?))[)]</span>") alls := str.FindAllStringSubmatch(result, -1) for _, j := range alls { temp, err := strconv.Atoi(j[1]) if err != nil { fmt.Println("string2int err:", err) } readCount += temp } str = regexp.MustCompile("post-comment-count\">评论[(](?s:(.*?))[)]</span>") alls = str.FindAllStringSubmatch(result, -1) for _, j := range alls { temp, err := strconv.Atoi(j[1]) if err != nil { fmt.Println("string2int err:", err) } commentCount += temp } str = regexp.MustCompile("post-digg-count\">推荐[(](?s:(.*?))[)]</span>") alls = str.FindAllStringSubmatch(result, -1) for _, j := range alls { temp, err := strconv.Atoi(j[1]) if err != nil { fmt.Println("string2int err:", err) } diggCount += temp } page <- index } //主要工作方法 func working(start, end int) { fmt.Printf("正在从%d到%d爬取中...\n", start, end) //channel通知主线程是否所有go都结束 page := make(chan int) //多线程go程同时爬取 for i := start; i <= end; i++ { go SpiderPageDB(i, page) } for i := start; i <= end; i++ { fmt.Printf("拉取到%d页\n", <-page) } } //入口函数 func main() { //输入爬取的起始页 var start, end int fmt.Print("startPos:") fmt.Scan(&start) fmt.Print("endPos:") fmt.Scan(&end) working(start, end) fmt.Println("阅读:", readCount) fmt.Println("评论:", commentCount) fmt.Println("推荐:", diggCount) } ``` **效果图如下**  **其他实例** golang爬虫爬取经典案例豆瓣，例子可以借鉴，正则要好好利用 ```go package main import ( "fmt" "io" "net/http" "os" "regexp" "strconv" ) func savToFile(index int, filmName, filmScore [][]string) { f, err := os.Create("第" + strconv.Itoa(index) + "页.txt") if err != nil { fmt.Println("os create err", err) return } defer f.Close() // 查出有多少条 n := len(filmName) // 先写抬头 名称 评分 f.WriteString("电影名称" + "\t\t\t" + "评分" + "\n") for i := 0; i < n; i++ { f.WriteString(filmName[i][1] + "\t\t\t" + filmScore[i][1] + "\n") } } func main() { var start, end int fmt.Print("请输入要爬取的起始页") fmt.Scan(&start) fmt.Print("请输入要爬取的终止页") fmt.Scan(&end) working(start, end) } func working(start int, end int) { fmt.Printf("正在爬取%d到%d页", start, end) for i := start; i <= end; i++ { SpiderPage(i) } } // 爬取一个豆瓣页面数据信息保存到文档 func SpiderPage(index int) { // 获取url url := "https://movie.douban.com/top250?start=" + strconv.Itoa((index-1)*25) + "&filter=" // 爬取url对应页面 result, err := HttpGet(url) if err != nil { fmt.Println("httpget err", err) return } //fmt.Println("result=", result) // 解析，编译正则表达式 ---电影名称 ret := regexp.MustCompile(`<img width="100" alt="(?s:(.*?))"`) filmName := ret.FindAllStringSubmatch(result, -1) for _, name := range filmName { fmt.Println("name", name[1]) } ret2 := regexp.MustCompile(`<span class="rating_num" property="v:average">(?s:(.*?))<`) filmScore := ret2.FindAllStringSubmatch(result, -1) for _, score := range filmScore { fmt.Println("score", score[1]) } savToFile(index, filmName, filmScore) } // 爬取指定url页面，返回result func HttpGet(url string) (result string, err error) { req, _ := http.NewRequest("GET", url, nil) // 设置头部信息 req.Header.Set("User-Agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/79.0.3945.130 Safari/537.36 OPR/66.0.3515.115") resp, err1 := (&http.Client{}).Do(req) //resp, err1 := http.Get(url) //此方法已经被豆瓣视为爬虫，返回状态吗为418，所以必须伪装头部用上述办法 if err1 != nil { err = err1 return } defer resp.Body.Close() buf := make([]byte, 4096) //循环爬取整页数据 for { n, err2 := resp.Body.Read(buf) if n == 0 { break } if err2 != nil && err2 != io.EOF { err = err2 return } result += string(buf[:n]) } return } ```