带有prismjs的静态html生成-如何启用行号？

Question

我使用node.js从代码中生成静态html文件，并使用prismjs格式化它们。在我的应用程序中，我无法访问支持Javascript的HTML呈现程序(我使用的是'htmllite')。所以我需要能够生成不需要Javascript的HTML。

const Prism = require('prismjs');
const loadLanguages = require('prismjs/components/');
loadLanguages(['csharp']);
const code = '<a bunch of C# code>';
const html = Prism.highlight(code, Prism.languages.csharp, 'csharp');

这个很好用。但我想使用line-numbers插件，不知道如何使它工作。我的<pre>有line-numbers类，我的左边框更大，但没有行号。

Answer 1

PrismJS需要DOM才能让大多数插件工作。在查看plugins/line-numbers/prism-line-numbers.js#L109内部的代码之后，我们可以看到行号只是一个带有class="line-numbers-rows"的span元素，它包含每个行的空span。我们可以在不使用DOM的情况下模拟这种行为，只需使用与prism-line-numbers相同的正则表达式来获取行号，然后组成一个具有span.line-numbers-rows的html代码的字符串，并为每一行添加一个空字符串<span></span>。

Prism.highlight只运行两个钩子，before-tokenize和after-tokenize。我们将使用after-tokenize组成一个lineNumbersWrapper字符串，其中包含span.line-numbers-rows元素和空的span行元素：

const Prism = require('prismjs');
const loadLanguages = require('prismjs/components/');
loadLanguages(['csharp']);

const code = `Console.WriteLine();
Console.WriteLine("Demo: Prism line-numbers plugin with nodejs");`;

// https://github.com/PrismJS/prism/blob/master/plugins/line-numbers/prism-line-numbers.js#L109
var NEW_LINE_EXP = /\n(?!$)/g;
var lineNumbersWrapper;

Prism.hooks.add('after-tokenize', function (env) {
  var match = env.code.match(NEW_LINE_EXP);
  var linesNum = match ? match.length + 1 : 1;
  var lines = new Array(linesNum + 1).join('<span></span>');

  lineNumbersWrapper = `<span aria-hidden="true" class="line-numbers-rows">${lines}</span>`;
});

const formated = Prism.highlight(code, Prism.languages.csharp, 'csharp');
const html = formated + lineNumbersWrapper;

console.log(html);

这将产生以下结果：

Console<span class="token punctuation">.</span><span class="token function">WriteLine</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
Console<span class="token punctuation">.</span><span class="token function">WriteLine</span><span class="token punctuation">(</span><span class="token string">"Demo: Generate invalid numbers"</span><span class="token punctuation">)</span><span class="token punctuation">;</span><span aria-hidden="true" class="line-numbers-rows"><span></span><span></span></span>

它的末尾有span.line-numbers-rows：

<span aria-hidden="true" class="line-numbers-rows">
  <span></span>
  <span></span>
</span>

现在，如果我们在pre.language-csharp.line-numbers code.language-csharp元素中使用该输出，我们将得到正确的行号结果。检查这个只有themes/prism.css和plugins/line-numbers/prism-line-numbers.css的themes/prism.css，并使用上面输出的代码正确地显示行号。

请注意，每一行(第一行除外)都必须标记代码才能正确显示，这是因为我们在pre.code块中，但我想您已经知道了。

更新

如果您不依赖CSS，并且您只想在每一行之前添加一个行号，那么您可以通过拆分所有行来添加一个行，并在开始时使用index + 1添加一个空格填充的padStart。

const Prism = require('prismjs');
const loadLanguages = require('prismjs/components/');
loadLanguages(['csharp']);

const code = `Console.WriteLine();
Console.WriteLine("Demo: Prism line-numbers plugin with nodejs");`;

const formated = Prism.highlight(code, Prism.languages.csharp, 'csharp');

const html = formated
  .split('\n')
  .map((line, num) => `${(num + 1).toString().padStart(4, ' ')}. ${line}`)
  .join('\n');

console.log(html);

将产出：

   1. Console<span class="token punctuation">.</span><span class="token function">WriteLine</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
   2. Console<span class="token punctuation">.</span><span class="token function">WriteLine</span><span class="token punctuation">(</span><span class="token string">"Demo: Prism line-numbers plugin with nodejs"</span><span class="token punctuation">)</span><span class="token punctuation">;</span>

Answer 2

我有一个带有代码片段的React网站，我使用了类似于以下方式的prismjs节点模块：

SourceCode.js

import * as Prism from "prismjs";
export default function SourceCode(props) {
    return (
        <div>
            <div style={{ maxWidth: 900 }}>
                <pre className="language-javascript" style={{ backgroundColor: "#272822", fontSize: "0.8em" }}>
                    <code
                        style={{ fontFamily: "Consolas,Monaco,'Andale Mono','Ubuntu Mono',monospace" }}
                        dangerouslySetInnerHTML={{
                            __html: Prism.highlight(props.code, Prism.languages.javascript, "javascript"),
                        }}
                    />
                </pre>
            </div>
        </div>
    );
};

然后我决定添加行号插件，我很难弄清楚如何让它与Node.js一起工作并做出反应。问题是行号使用DOM，而不是简单地在Node.js中使用DOM。

我终于做了什么。我卸载了prismjs模块，并以一种旧的方式完成了它:)。

index.html

<html lang="en-us">
    <head>
        <meta charset="utf-8" />
        <meta content="text/html; charset=utf-8" http-equiv="Content-Type" />
        <title>SciChart Web Demo</title>
        <link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Roboto:300,400,500,700&display=swap" />
        <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/prism/1.21.0/themes/prism-okaidia.min.css" />
        <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/prism/1.21.0/plugins/line-numbers/prism-line-numbers.min.css" />
        <script async type="text/javascript" src="bundle.js"></script>
    </head>
    <body>
        <div id="react-root"></div>
        <script>
            window.Prism = window.Prism || {};
            Prism.manual = true;
        </script>
        <script src="https://cdnjs.cloudflare.com/ajax/libs/prism/1.21.0/prism.min.js"></script>
        <script src="https://cdnjs.cloudflare.com/ajax/libs/prism/1.21.0/plugins/line-numbers/prism-line-numbers.min.js"></script>
    </body>
</html>

SourceCode.js

import * as React from "react";

export default function SourceCode(props) {
    React.useEffect(() => {
        window.Prism.highlightAll();
    }, []);
    return (
        <div>
            <div style={{ maxWidth: 900 }}>
                <pre
                    className="language-javascript line-numbers"
                    style={{ backgroundColor: "#272822", fontSize: "0.8em" }}
                >
                    <code style={{ fontFamily: "Consolas,Monaco,'Andale Mono','Ubuntu Mono',monospace" }}>
                        {props.code}
                    </code>
                </pre>
            </div>
        </div>
    );
};

Answer 3

也许这能帮你：

错误代码：

链接

(代码行超过堆栈溢出的限制!)

​

​

Codepen工作正常：

链接

(代码行超过堆栈溢出的限制!)

​

​

在两者之间的变化：

​

pre.line-numbers {
	position: relative;
	padding-left: 3.8em;
	counter-reset: linenumber;
}

pre.line-numbers>code {
	position: relative;
}

.line-numbers .line-numbers-rows {
	position: absolute;
	pointer-events: none;
	top: 0;
	font-size: 100%;
	left: -3.8em;
	width: 3em;
	/* works for line-numbers below 1000 lines */
	letter-spacing: -1px;
	border-right: 1px solid #999;
	-webkit-user-select: none;
	-moz-user-select: none;
	-ms-user-select: none;
	user-select: none;
}

.line-numbers-rows>span {
	pointer-events: none;
	display: block;
	counter-increment: linenumber;
}

.line-numbers-rows>span:before {
	content: counter(linenumber);
	color: #999;
	display: block;
	padding-right: 0.8em;
	text-align: right;
}

​