英文字典

以前在Java中网页抓取，然后利用正则表示式抽取文本，非常方便。学习go语言时，也产生了相同的想法，就以英语查单词为例，做了个ICIBA版的英文字典。

代码如下：

package main

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

var exit string = "-q" // default exit code

const (
	ICIBA      string = "http://www.iciba.com/"
	MEANING_CN string = `\s*(([^<]*\s*)*)`
)

func solveArgs() {
	flag.Parse()
	args := flag.Args()

	if len(args) > 0 {
		exit = args[0]
	}
}

func search(keyword string) {
	keyword = strings.TrimSpace(keyword)
	keyword = strings.Replace(keyword, " ", "_", 0) // more than one word, the iciba join it with _
	resp, err := http.Get(ICIBA + keyword)
	if err != nil {
		fmt.Println("Error raised when query the word, the message is " + err.Error())
	} else {
		defer resp.Body.Close()
		body, err := ioutil.ReadAll(resp.Body)
		if err != nil {
			fmt.Println("http read error")
			return
		}
		reg, _ := regexp.Compile(MEANING_CN)
		content := reg.FindSubmatch(body)
		if content != nil {
			reg, _ = regexp.Compile(`<(/?)label>\s*`)
			val := reg.ReplaceAll(content[1], []byte(""))
			fmt.Println("= " + string(val))
		} else {
			fmt.Println("Not found, Pls input again.")
		}
	}
}

func main() {
	solveArgs()

	fmt.Println("Welcome! This is Jay's English dictionary.\n")
	fmt.Println("Please feel free to input any word and the program will help you to find the Chinese meaning of your input.")
	running := true
	reader := bufio.NewReader(os.Stdin)
	for running {
		fmt.Print("\n> ")
		data, _, _ := reader.ReadLine()
		command := string(data)
		if command == exit {
			fmt.Println("See you!")
			running = false
		} else {
			search(command)
		}
	}
}