java - 从表示为字符串的 HTML 中提取内容

Question

我有一个 Big html in String 变量，我想获取 div 的内容。我不能依赖正则表达式，因为它可以有嵌套的 div。所以，假设我有以下字符串 -

String test = "<div><div id=\"mainContent\">foo bar<div>good best better</div>  <div>test test</div></div><div>foo bar</div></div>";

那么我怎样才能用一个简单的java程序得到这个 -

<div id="mainContent">foo bar<div>good best better</div>  <div>test test</div></div>

嗯，我的方法是这样的(可能很可怕，仍在努力纠正)-

public static void main(String[] args) {
            int count = 1;
        int fl = 0;
        String s = "<div><div id=\"mainContent\">foo bar<div>good best better</div>  <div>test test</div></div><div>foo bar</div></div>";
        String tmp = s;
        int len = s.length();
        for (int i=0; i<len; i++){
            int st = s.indexOf("div>");
            if(st > -1) {
                char c = s.charAt(st-1);
                if(c == '/') {
                    count--; 
                } else {
                    count++;
                }
                s = s.substring(st+4);
                System.out.println(s);
                i = i + st;
                System.out.println(c + " -- " + st + " -- " + count + " -- " + i);  
                if (count == 0) {
                    fl = i;
                    break;
                }
            }
        }
        System.out.println("final ind - " + fl);
        s = tmp.substring(0, fl + 4);
        System.out.println("final String - " + s);
}

Answer 1

我建议使用JSoup解析 HTML 并找到您要查找的内容。

它肯定满足简单要求。只需几行代码即可完成您想要的事情!

jsoup is a Java library for working with real-world HTML. It provides a very convenient API for extracting and manipulating data, using the best of DOM, CSS, and jquery-like methods.

jsoup implements the WHATWG HTML5 specification, and parses HTML to the same DOM as modern browsers do.

scrape and parse HTML from a URL, file, or string

find and extract data, using DOM traversal or CSS selectors

jsoup is designed to deal with all varieties of HTML found in the wild; from pristine and validating, to invalid tag-soup; jsoup will create a sensible parse tree.

使用selector syntax使查找和提取数据变得极其简单。

public static void main(final String[] args)
{
    final String s = "<div><div id=\"mainContent\">foo bar<div>good best better</div>  <div>test test</div></div><div>foo bar</div></div>";
    final Document d = Jsoup.parse(s);
    final Elements e = d.select("#mainContent");
    System.out.println(e.get(0));
}

输出

  <div id="mainContent">
   foo bar
   <div>
    good best better
   </div> 
   <div>
    test test
   </div>
  </div>

没有比这更简单的了!