使用jsoup将html转换为纯文本时如何保留换行符？-Java 学习之路

我有以下代码：

public class NewClass {
     public String noTags(String str){
         return Jsoup.parse(str).text();
     }


     public static void main(String args[]) {
         String strings="<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.0 Transitional//EN \">" +
         "<HTML> <HEAD> <TITLE></TITLE> <style>body{ font-size: 12px;font-family: verdana, arial, helvetica, sans-serif;}</style> </HEAD> <BODY><p><b>hello world</b></p><p><br><b>yo</b> <a href=\"http://google.com\">googlez</a></p></BODY> </HTML> ";

         NewClass text = new NewClass();
         System.out.println((text.noTags(strings)));
}

我有结果：

hello world yo googlez

但我想打破界限：

hello world
yo googlez

我看了jsoup's TextNode#getWholeText()但我无法弄清楚如何使用它 .

如果我解析的标记中有 <br> ，我如何在结果输出中获得换行符？

15 回答

保留换行符的真正解决方案应该是这样的：

public static String br2nl(String html) {
    if(html==null)
        return html;
    Document document = Jsoup.parse(html);
    document.outputSettings(new Document.OutputSettings().prettyPrint(false));//makes html() preserve linebreaks and spacing
    document.select("br").append("\\n");
    document.select("p").prepend("\\n\\n");
    String s = document.html().replaceAll("\\\\n", "\n");
    return Jsoup.clean(s, "", Whitelist.none(), new Document.OutputSettings().prettyPrint(false));
}

它满足以下要求：

如果原始html包含换行符（\ n），则会保留它
如果原始html包含br或p标签，则会将它们转换为换行符（\ n） .

回复于 2024-04-20T13:09:09+08:00

同

Jsoup.parse("A\nB").text();

你有输出

"A B"

并不是

A

B

为此，我正在使用：

descrizione = Jsoup.parse(html.replaceAll("(?i)<br[^>]*>", "br2n")).text();
text = descrizione.replaceAll("br2n", "\n");

回复于 2024-04-20T13:09:09+08:00

Jsoup.clean(unsafeString, "", Whitelist.none(), new OutputSettings().prettyPrint(false));

我们在这里使用这种方法：

public static String clean(String bodyHtml,
                       String baseUri,
                       Whitelist whitelist,
                       Document.OutputSettings outputSettings)

通过传递 Whitelist.none() ，我们确保删除所有HTML .

通过传递 new OutputSettings().prettyPrint(false) ，我们确保不重新格式化输出并保留换行符 .

回复于 2024-04-20T13:09:09+08:00

使用jsoup尝试这个：

public static String cleanPreserveLineBreaks(String bodyHtml) {

    // get pretty printed html with preserved br and p tags
    String prettyPrintedBodyFragment = Jsoup.clean(bodyHtml, "", Whitelist.none().addTags("br", "p"), new OutputSettings().prettyPrint(true));
    // get plain text with preserved line breaks by disabled prettyPrint
    return Jsoup.clean(prettyPrintedBodyFragment, "", Whitelist.none(), new OutputSettings().prettyPrint(false));
}

回复于 2024-04-20T13:09:09+08:00

您可以遍历给定元素

public String convertNodeToText(Element element)
{
    final StringBuilder buffer = new StringBuilder();

    new NodeTraversor(new NodeVisitor() {
        boolean isNewline = true;

        @Override
        public void head(Node node, int depth) {
            if (node instanceof TextNode) {
                TextNode textNode = (TextNode) node;
                String text = textNode.text().replace('\u00A0', ' ').trim();                    
                if(!text.isEmpty())
                {                        
                    buffer.append(text);
                    isNewline = false;
                }
            } else if (node instanceof Element) {
                Element element = (Element) node;
                if (!isNewline)
                {
                    if((element.isBlock() || element.tagName().equals("br")))
                    {
                        buffer.append("\n");
                        isNewline = true;
                    }
                }
            }                
        }

        @Override
        public void tail(Node node, int depth) {                
        }                        
    }).traverse(element);        

    return buffer.toString();               
}

并为您的代码

String result = convertNodeToText(JSoup.parse(html))

回复于 2024-04-20T13:09:09+08:00

text = Jsoup.parse(html.replaceAll("(?i)<br[^>]*>", "br2n")).text();
text = descrizione.replaceAll("br2n", "\n");

如果html本身不包含“br2n”，则有效

所以，

text = Jsoup.parse(html.replaceAll("(?i)<br[^>]*>", "<pre>\n</pre>")).text();

工作更可靠，更容易 .

回复于 2024-04-20T13:09:09+08:00

这是我将html翻译成文本的版本（实际上是user121196答案的修改版本） .

这不仅可以保留换行符，还可以格式化文本并删除过多的换行符，HTML转义符号，并且您将从HTML中获得更好的结果（在我的情况下，我是通过邮件接收它） .

它最初是用Scala编写的，但您可以轻松地将其更改为Java

def html2text( rawHtml : String ) : String = {

    val htmlDoc = Jsoup.parseBodyFragment( rawHtml, "/" )
    htmlDoc.select("br").append("\\nl")
    htmlDoc.select("div").append("\\nl")
    htmlDoc.select("p").prepend("\\nl\\nl")
    htmlDoc.select("p").append("\\nl\\nl")

    org.jsoup.parser.Parser.unescapeEntities(
        Jsoup.clean(
          htmlDoc.html(),
          "",
          Whitelist.none(),
          new org.jsoup.nodes.Document.OutputSettings().prettyPrint(true)
        ),false
    ).
    replaceAll("\\\\nl", "\n").
    replaceAll("\r","").
    replaceAll("\n\\s+\n","\n").
    replaceAll("\n\n+","\n\n").     
    trim()      
}

回复于 2024-04-20T13:09:09+08:00

86
对于更复杂的HTML，上述解决方案中没有一个能够正常工作;我能够在保留换行符的同时成功完成转换：
```
Document document = Jsoup.parse(myHtml);
String text = new HtmlToPlainText().getPlainText(document);
```
（版本1.10.3）
回复于 2024-04-20T13:09:09+08:00

试试这个：

public String noTags(String str){
    Document d = Jsoup.parse(str);
    TextNode tn = new TextNode(d.body().html(), "");
    return tn.getWholeText();
}

回复于 2024-04-20T13:09:09+08:00

21
使用 textNodes() 获取文本节点的列表 . 然后将它们与 \n 连接为分隔符 . 这是我使用的一些scala代码，java端口应该很简单：
```
val rawTxt = doc.body().getElementsByTag("div").first.textNodes()
                    .asScala.mkString("
\n")
```
回复于 2024-04-20T13:09:09+08:00

基于其他答案和对这个问题的评论，似乎大多数人来到这里真的在寻找一个通用的解决方案，它将提供HTML文档的格式良好的纯文本表示 . 我知道我是 .

幸运的是，JSoup已经提供了一个非常全面的例子来说明如何实现这个目标：HtmlToPlainText.java

示例 FormattingVisitor 可以很容易地根据您的喜好进行调整，并处理大多数块元素和换行 .

为了避免链接腐烂，这里完全是_2595541的解决方案：

package org.jsoup.examples;

import org.jsoup.Jsoup;
import org.jsoup.helper.StringUtil;
import org.jsoup.helper.Validate;
import org.jsoup.nodes.Document;
import org.jsoup.nodes.Element;
import org.jsoup.nodes.Node;
import org.jsoup.nodes.TextNode;
import org.jsoup.select.Elements;
import org.jsoup.select.NodeTraversor;
import org.jsoup.select.NodeVisitor;

import java.io.IOException;

/**
 * HTML to plain-text. This example program demonstrates the use of jsoup to convert HTML input to lightly-formatted
 * plain-text. That is divergent from the general goal of jsoup's .text() methods, which is to get clean data from a
 * scrape.
 * <p>
 * Note that this is a fairly simplistic formatter -- for real world use you'll want to embrace and extend.
 * </p>
 * <p>
 * To invoke from the command line, assuming you've downloaded the jsoup jar to your current directory:</p>
 * <p><code>java -cp jsoup.jar org.jsoup.examples.HtmlToPlainText url [selector]</code></p>
 * where <i>url</i> is the URL to fetch, and <i>selector</i> is an optional CSS selector.
 * 
 * @author Jonathan Hedley, jonathan@hedley.net
 */
public class HtmlToPlainText {
    private static final String userAgent = "Mozilla/5.0 (jsoup)";
    private static final int timeout = 5 * 1000;

    public static void main(String... args) throws IOException {
        Validate.isTrue(args.length == 1 || args.length == 2, "usage: java -cp jsoup.jar org.jsoup.examples.HtmlToPlainText url [selector]");
        final String url = args[0];
        final String selector = args.length == 2 ? args[1] : null;

        // fetch the specified URL and parse to a HTML DOM
        Document doc = Jsoup.connect(url).userAgent(userAgent).timeout(timeout).get();

        HtmlToPlainText formatter = new HtmlToPlainText();

        if (selector != null) {
            Elements elements = doc.select(selector); // get each element that matches the CSS selector
            for (Element element : elements) {
                String plainText = formatter.getPlainText(element); // format that element to plain text
                System.out.println(plainText);
            }
        } else { // format the whole doc
            String plainText = formatter.getPlainText(doc);
            System.out.println(plainText);
        }
    }

    /**
     * Format an Element to plain-text
     * @param element the root element to format
     * @return formatted text
     */
    public String getPlainText(Element element) {
        FormattingVisitor formatter = new FormattingVisitor();
        NodeTraversor traversor = new NodeTraversor(formatter);
        traversor.traverse(element); // walk the DOM, and call .head() and .tail() for each node

        return formatter.toString();
    }

    // the formatting rules, implemented in a breadth-first DOM traverse
    private class FormattingVisitor implements NodeVisitor {
        private static final int maxWidth = 80;
        private int width = 0;
        private StringBuilder accum = new StringBuilder(); // holds the accumulated text

        // hit when the node is first seen
        public void head(Node node, int depth) {
            String name = node.nodeName();
            if (node instanceof TextNode)
                append(((TextNode) node).text()); // TextNodes carry all user-readable text in the DOM.
            else if (name.equals("li"))
                append("\n * ");
            else if (name.equals("dt"))
                append("  ");
            else if (StringUtil.in(name, "p", "h1", "h2", "h3", "h4", "h5", "tr"))
                append("\n");
        }

        // hit when all of the node's children (if any) have been visited
        public void tail(Node node, int depth) {
            String name = node.nodeName();
            if (StringUtil.in(name, "br", "dd", "dt", "p", "h1", "h2", "h3", "h4", "h5"))
                append("\n");
            else if (name.equals("a"))
                append(String.format(" <%s>", node.absUrl("href")));
        }

        // appends text to the string builder with a simple word wrap method
        private void append(String text) {
            if (text.startsWith("\n"))
                width = 0; // reset counter if starts with a newline. only from formats above, not in natural text
            if (text.equals(" ") &&
                    (accum.length() == 0 || StringUtil.in(accum.substring(accum.length() - 1), " ", "\n")))
                return; // don't accumulate long runs of empty spaces

            if (text.length() + width > maxWidth) { // won't fit, needs to wrap
                String words[] = text.split("\\s+");
                for (int i = 0; i < words.length; i++) {
                    String word = words[i];
                    boolean last = i == words.length - 1;
                    if (!last) // insert a space if not the last word
                        word = word + " ";
                    if (word.length() + width > maxWidth) { // wrap and reset counter
                        accum.append("\n").append(word);
                        width = word.length();
                    } else {
                        accum.append(word);
                        width += word.length();
                    }
                }
            } else { // fits as is, without need to wrap text
                accum.append(text);
                width += text.length();
            }
        }

        @Override
        public String toString() {
            return accum.toString();
        }
    }
}

回复于 2024-04-20T13:09:09+08:00

使用jsoup尝试这个：

doc.outputSettings(new OutputSettings().prettyPrint(false));

    //select all <br> tags and append \n after that
    doc.select("br").after("\\n");

    //select all <p> tags and prepend \n before that
    doc.select("p").before("\\n");

    //get the HTML from the document, and retaining original new lines
    String str = doc.html().replaceAll("\\\\n", "\n");

回复于 2024-04-20T13:09:09+08:00

/**
 * Recursive method to replace html br with java \n. The recursive method ensures that the linebreaker can never end up pre-existing in the text being replaced.
 * @param html
 * @param linebreakerString
 * @return the html as String with proper java newlines instead of br
 */
public static String replaceBrWithNewLine(String html, String linebreakerString){
    String result = "";
    if(html.contains(linebreakerString)){
        result = replaceBrWithNewLine(html, linebreakerString+"1");
    } else {
        result = Jsoup.parse(html.replaceAll("(?i)<br[^>]*>", linebreakerString)).text(); // replace and html line breaks with java linebreak.
        result = result.replaceAll(linebreakerString, "\n");
    }
    return result;
}

通过调用有问题的html，包含br，以及您希望用作临时换行占位符的任何字符串来使用 . 例如：

replaceBrWithNewLine(element.html(), "br2n")

递归将确保您用作换行符/换行符占位符的字符串永远不会实际位于源html中，因为它将继续添加“1”，直到html中找不到链接断开器占位符字符串 . 它没有Jsoup.clean方法似乎遇到特殊字符的格式问题 .

回复于 2024-04-20T13:09:09+08:00

基于user121196 's and Green Beret'回答 select 和 <pre> ，对我有用的唯一解决方案是：

org.jsoup.nodes.Element elementWithHtml = ....
elementWithHtml.select("br").append("<pre>\n</pre>");
elementWithHtml.select("p").prepend("<pre>\n\n</pre>");
elementWithHtml.text();

回复于 2024-04-20T13:09:09+08:00

3
在Jsoup v1.11.2上，我们现在可以使用 Element.wholeText() .

示例代码：
```
String cleanString = Jsoup.parse(htmlString).wholeText();
```
user121196's answer仍然有效 . 但 wholeText() 保留了文本的对齐方式 .
回复于 2024-04-20T13:09:09+08:00

使用jsoup将html转换为纯文本时如何保留换行符？

15 回答

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