跨平台开发不再是困扰：学习Go语言

package main

import (
    "fmt"
    "net/http"
    "strings"
    "golang.org/x/net/html"
)

func main() {
    url := "http://example.com" //待爬取的网址
    links, err := ExtractLinks(url)
    if err != nil {
        fmt.Println("Error:", err)
        return
    }
    fmt.Println(links)
}

func ExtractLinks(url string) ([]string, error) {
    resp, err := http.Get(url)
    if err != nil {
        return nil, err
    }
    defer resp.Body.Close()

    doc, err := html.Parse(resp.Body)
    if err != nil {
        return nil, err
    }

    var links []string
    visitNode := func(n *html.Node) {
        if n.Type == html.ElementNode && n.Data == "a" {
            for _, a := range n.Attr {
                if a.Key == "href" {
                    link := a.Val
                    if !strings.HasPrefix(link, "http") {
                        link = url + link
                    }
                    links = append(links, link)
                }
            }
        }
    }
    preOrder(doc, visitNode)
    return links, nil
}

func preOrder(n *html.Node, f func(n *html.Node)) {
    if n != nil {
        f(n)
        for c := n.FirstChild; c != nil; c = c.NextSibling {
            preOrder(c, f)
        }
    }
}