博客园的markdown功能使用的是highlight.js，没有行号和显示相应编程语言的功能，只好自己将其改造了一下(将这两种功能一并实现了)~
先看一下效果，再详细介绍方法~
先找到一篇markdown模式下写的文章，然后打开Chrome，依次使用 F12 -> network -> filter ".js"，可知 代码高亮插件是 highlight.js.
尝试了很多方法，最后选择了开源的插件 highlightjs-line-numbers.js，其原理是生成一个新的table，增加tr、 td标签, 并设置border为none。
该插件官方文档中提到的方法为:
<script src="http://cdn.jsdelivr.net/npm/highlightjs-line-numbers.js@2.6.0/dist/highlightjs-line-numbers.min.js"></script> <script> hljs.initHighlightingOnLoad(); hljs.initLineNumbersOnLoad(); <script> 调整markdown的相关css接着按需要改进一下markdown的样式，将下面内容贴到页面定制css一栏即可。
.cnblogs-markdown .hljs { border: none !important; } #cnblogs_post_body th, #cnblogs_post_body td, .cnblogs-post-body th, .cnblogs-post-body td { border: none !important; padding: 0; } .postCon { font-size: 15px; } .cnblogs-markdown .hljs, .cnblogs-post-body .hljs { font-family: "Consolas",sans-serif !important; font-size: 15px! important; } .cnblogs-markdown .hljs, .cnblogs-post-body .hljs { font-family: "Courier New",sans-serif!important; font-size: 15px!important; line-height: 1.5!important; padding: 5px!important; } #cnblogs_post_body table, .cnblogs-post-body table { border: none !important; border-collapse: collapse; word-break: break-word; } 实现加代码行号、显示代码所用语言的具体js代码然后在页脚HTML中加入如下js代码~
<script> if($(".cnblogs-post-body pre > code").length > 0) setCodeRowWithLang($(".cnblogs-post-body pre")); else setCodeRowWithLang($(".cnblogs-markdown pre")); // markdown模式下为代码加入行号, 调用插件highlightjs-line-numbers.js hljs.initHighlightingOnLoad(); hljs.initLineNumbersOnLoad(); }); function setCodeRowWithLang(pre) { // var pre = $(".cnblogs-post-body pre"); // 选中需要处理的代码块, 如果不是首页，选择器为 .cnblogs-markdown pre if (pre && pre.length) { pre.each(function () { var item = $(this); var lang = item[0].className; //判断高亮的语言 var langMap = { "html": "HTML", "xml": "XML", "svg": "SVG", "mathml": "MathML", "css": "CSS", "clike": "C-like", "js": "JavaScript", "abap": "ABAP", "apacheconf": "Apache Configuration", "apl": "APL", "arff": "ARFF", "asciidoc": "AsciiDoc", "adoc": "AsciiDoc", "asm6502": "6502 Assembly", "aspnet": "ASP.NET (C#)", "autohotkey": "AutoHotkey", "autoit": "AutoIt", "shell": "Bash", "basic": "BASIC", "csharp": "C#", "dotnet": "C#", "cpp": "C++", "cil": "CIL", "csp": "Content-Security-Policy", "css-extras": "CSS Extras", "django": "Django/Jinja2", "jinja2": "Django/Jinja2", "dockerfile": "Docker", "erb": "ERB", "fsharp": "F#", "gcode": "G-code", "gedcom": "GEDCOM", "glsl": "GLSL", "gml": "GameMaker Language", "gamemakerlanguage": "GameMaker Language", "graphql": "GraphQL", "hcl": "HCL", "http": "HTTP", "hpkp": "HTTP Public-Key-Pins", "hsts": "HTTP Strict-Transport-Security", "ichigojam": "IchigoJam", "inform7": "Inform 7", "javastacktrace": "Java stack trace", "json": "JSON", "jsonp": "JSONP", "latex": "LaTeX", "emacs": "Lisp", "elisp": "Lisp", "emacs-lisp": "Lisp", "lolcode": "LOLCODE", "markup-templating": "Markup templating", "matlab": "MATLAB", "mel": "MEL", "n1ql": "N1QL", "n4js": "N4JS", "n4jsd": "N4JS", "nand2tetris-hdl": "Nand To Tetris HDL", "nasm": "NASM", "nginx": "nginx", "nsis": "NSIS", "objectivec": "Objective-C", "ocaml": "OCaml", "opencl": "OpenCL", "parigp": "PARI/GP", "objectpascal": "Object Pascal", "php": "PHP", "php-extras": "PHP Extras", "plsql": "PL/SQL", "powershell": "PowerShell", "properties": ".properties", "protobuf": "Protocol Buffers", "q": "Q (kdb+ database)", "jsx": "React JSX", "tsx": "React TSX", "renpy": "Ren'py", "rest": "reST (reStructuredText)", "sas": "SAS", "sass": "Sass (Sass)", "scss": "Sass (Scss)", "sql": "SQL", "soy": "Soy (Closure Template)", "tap": "TAP", "toml": "TOML", "tt2": "Template Toolkit 2", "ts": "TypeScript", "vbnet": "VB.Net", "vhdl": "VHDL", "vim": "vim", "visual-basic": "Visual Basic", "vb": "Visual Basic", "wasm": "WebAssembly", "wiki": "Wiki markup", "xeoracube": "XeoraCube", "xojo": "Xojo (REALbasic)", "xquery": "XQuery", "yaml": "YAML" }; var displayLangText = ""; if (lang in langMap) displayLangText = langMap[lang]; else displayLangText = lang; // console.log(lang); item.find('.hljs').prepend('<div top="0px" right="10px" position="relative"><a href="javascript:void(0);"></a> <font title="当前Code所用语言">' + displayLangText + '</font></div>'); }); }; } </script>上述js函数setCodeRowWithLang()对文章内容和博客首页都是有效的~