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<div id="column1" data-id="punycode" class="interior"> 90 <header> 91 <div class="header-container"> 92 <h1>Node.js v14.20.1 documentation</h1> 93 <button class="theme-toggle-btn" id="theme-toggle-btn" title="Toggle dark mode/light mode" aria-label="Toggle dark mode/light mode" hidden> 94 <svg xmlns="http://www.w3.org/2000/svg" class="icon dark-icon" height="24" width="24"> 95 <path fill="none" d="M0 0h24v24H0z" /> 96 <path d="M11.1 12.08c-2.33-4.51-.5-8.48.53-10.07C6.27 2.2 1.98 6.59 1.98 12c0 .14.02.28.02.42.62-.27 1.29-.42 2-.42 1.66 0 3.18.83 4.1 2.15A4.01 4.01 0 0111 18c0 1.52-.87 2.83-2.12 3.51.98.32 2.03.5 3.11.5 3.5 0 6.58-1.8 8.37-4.52-2.36.23-6.98-.97-9.26-5.41z"/> 97 <path d="M7 16h-.18C6.4 14.84 5.3 14 4 14c-1.66 0-3 1.34-3 3s1.34 3 3 3h3c1.1 0 2-.9 2-2s-.9-2-2-2z"/> 98 </svg> 99 <svg xmlns="http://www.w3.org/2000/svg" class="icon light-icon" height="24" width="24"> 100 <path d="M0 0h24v24H0z" fill="none" /> 101 <path d="M6.76 4.84l-1.8-1.79-1.41 1.41 1.79 1.79 1.42-1.41zM4 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href="https://nodejs.org/docs/latest-v4.x/api/punycode.html">4.x</a></li> 134<li><a href="https://nodejs.org/docs/latest-v0.12.x/api/punycode.html">0.12.x</a></li> 135<li><a href="https://nodejs.org/docs/latest-v0.10.x/api/punycode.html">0.10.x</a></li></ol> 136 </li> 137 138 <li class="edit_on_github"><a href="https://github.com/nodejs/node/edit/master/doc/api/punycode.md">Edit on GitHub</a></li> 139 </ul> 140 </div> 141 <hr> 142 </header> 143 144 <details id="toc" open><summary>Table of contents</summary><ul> 145<li><span class="stability_0"><a href="#punycode_punycode">Punycode</a></span> 146<ul> 147<li><a href="#punycode_punycode_decode_string"><code>punycode.decode(string)</code></a></li> 148<li><a href="#punycode_punycode_encode_string"><code>punycode.encode(string)</code></a></li> 149<li><a href="#punycode_punycode_toascii_domain"><code>punycode.toASCII(domain)</code></a></li> 150<li><a href="#punycode_punycode_tounicode_domain"><code>punycode.toUnicode(domain)</code></a></li> 151<li><a href="#punycode_punycode_ucs2"><code>punycode.ucs2</code></a> 152<ul> 153<li><a href="#punycode_punycode_ucs2_decode_string"><code>punycode.ucs2.decode(string)</code></a></li> 154<li><a href="#punycode_punycode_ucs2_encode_codepoints"><code>punycode.ucs2.encode(codePoints)</code></a></li> 155</ul> 156</li> 157<li><a href="#punycode_punycode_version"><code>punycode.version</code></a></li> 158</ul> 159</li> 160</ul></details> 161 162 <div id="apicontent"> 163 <h2>Punycode<span><a class="mark" href="#punycode_punycode" id="punycode_punycode">#</a></span></h2> 164<div class="api_metadata"> 165<span>Deprecated since: v7.0.0</span> 166</div> 167 168<p></p><div class="api_stability api_stability_0"><a href="documentation.html#documentation_stability_index">Stability: 0</a> - Deprecated</div><p></p> 169<p><strong>Source Code:</strong> <a href="https://github.com/nodejs/node/blob/v14.20.1/lib/punycode.js">lib/punycode.js</a></p> 170<p><strong>The version of the punycode module bundled in Node.js is being deprecated</strong>. 171In a future major version of Node.js this module will be removed. Users 172currently depending on the <code>punycode</code> module should switch to using the 173userland-provided <a href="https://github.com/bestiejs/punycode.js">Punycode.js</a> module instead. For punycode-based URL 174encoding, see <a href="url.html#url_url_domaintoascii_domain"><code>url.domainToASCII</code></a> or, more generally, the 175<a href="url.html#url_the_whatwg_url_api">WHATWG URL API</a>.</p> 176<p>The <code>punycode</code> module is a bundled version of the <a href="https://github.com/bestiejs/punycode.js">Punycode.js</a> module. It 177can be accessed using:</p> 178<pre><code class="language-js"><span class="hljs-keyword">const</span> punycode = <span class="hljs-built_in">require</span>(<span class="hljs-string">'punycode'</span>);</code></pre> 179<p><a href="https://tools.ietf.org/html/rfc3492">Punycode</a> is a character encoding scheme defined by RFC 3492 that is 180primarily intended for use in Internationalized Domain Names. Because host 181names in URLs are limited to ASCII characters only, Domain Names that contain 182non-ASCII characters must be converted into ASCII using the Punycode scheme. 183For instance, the Japanese character that translates into the English word, 184<code>'example'</code> is <code>'例'</code>. The Internationalized Domain Name, <code>'例.com'</code> (equivalent 185to <code>'example.com'</code>) is represented by Punycode as the ASCII string 186<code>'xn--fsq.com'</code>.</p> 187<p>The <code>punycode</code> module provides a simple implementation of the Punycode standard.</p> 188<p>The <code>punycode</code> module is a third-party dependency used by Node.js and 189made available to developers as a convenience. Fixes or other modifications to 190the module must be directed to the <a href="https://github.com/bestiejs/punycode.js">Punycode.js</a> project.</p> 191<section><h3><code>punycode.decode(string)</code><span><a class="mark" href="#punycode_punycode_decode_string" id="punycode_punycode_decode_string">#</a></span></h3> 192<div class="api_metadata"> 193<span>Added in: v0.5.1</span> 194</div> 195<ul> 196<li><code>string</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 197</ul> 198<p>The <code>punycode.decode()</code> method converts a <a href="https://tools.ietf.org/html/rfc3492">Punycode</a> string of ASCII-only 199characters to the equivalent string of Unicode codepoints.</p> 200<pre><code class="language-js">punycode.<span class="hljs-title function_">decode</span>(<span class="hljs-string">'maana-pta'</span>); <span class="hljs-comment">// 'mañana'</span> 201punycode.<span class="hljs-title function_">decode</span>(<span class="hljs-string">'--dqo34k'</span>); <span class="hljs-comment">// '☃-⌘'</span></code></pre> 202</section><section><h3><code>punycode.encode(string)</code><span><a class="mark" href="#punycode_punycode_encode_string" id="punycode_punycode_encode_string">#</a></span></h3> 203<div class="api_metadata"> 204<span>Added in: v0.5.1</span> 205</div> 206<ul> 207<li><code>string</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 208</ul> 209<p>The <code>punycode.encode()</code> method converts a string of Unicode codepoints to a 210<a href="https://tools.ietf.org/html/rfc3492">Punycode</a> string of ASCII-only characters.</p> 211<pre><code class="language-js">punycode.<span class="hljs-title function_">encode</span>(<span class="hljs-string">'mañana'</span>); <span class="hljs-comment">// 'maana-pta'</span> 212punycode.<span class="hljs-title function_">encode</span>(<span class="hljs-string">'☃-⌘'</span>); <span class="hljs-comment">// '--dqo34k'</span></code></pre> 213</section><section><h3><code>punycode.toASCII(domain)</code><span><a class="mark" href="#punycode_punycode_toascii_domain" id="punycode_punycode_toascii_domain">#</a></span></h3> 214<div class="api_metadata"> 215<span>Added in: v0.6.1</span> 216</div> 217<ul> 218<li><code>domain</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 219</ul> 220<p>The <code>punycode.toASCII()</code> method converts a Unicode string representing an 221Internationalized Domain Name to <a href="https://tools.ietf.org/html/rfc3492">Punycode</a>. Only the non-ASCII parts of the 222domain name will be converted. Calling <code>punycode.toASCII()</code> on a string that 223already only contains ASCII characters will have no effect.</p> 224<pre><code class="language-js"><span class="hljs-comment">// encode domain names</span> 225punycode.<span class="hljs-title function_">toASCII</span>(<span class="hljs-string">'mañana.com'</span>); <span class="hljs-comment">// 'xn--maana-pta.com'</span> 226punycode.<span class="hljs-title function_">toASCII</span>(<span class="hljs-string">'☃-⌘.com'</span>); <span class="hljs-comment">// 'xn----dqo34k.com'</span> 227punycode.<span class="hljs-title function_">toASCII</span>(<span class="hljs-string">'example.com'</span>); <span class="hljs-comment">// 'example.com'</span></code></pre> 228</section><section><h3><code>punycode.toUnicode(domain)</code><span><a class="mark" href="#punycode_punycode_tounicode_domain" id="punycode_punycode_tounicode_domain">#</a></span></h3> 229<div class="api_metadata"> 230<span>Added in: v0.6.1</span> 231</div> 232<ul> 233<li><code>domain</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 234</ul> 235<p>The <code>punycode.toUnicode()</code> method converts a string representing a domain name 236containing <a href="https://tools.ietf.org/html/rfc3492">Punycode</a> encoded characters into Unicode. Only the <a href="https://tools.ietf.org/html/rfc3492">Punycode</a> 237encoded parts of the domain name are be converted.</p> 238<pre><code class="language-js"><span class="hljs-comment">// decode domain names</span> 239punycode.<span class="hljs-title function_">toUnicode</span>(<span class="hljs-string">'xn--maana-pta.com'</span>); <span class="hljs-comment">// 'mañana.com'</span> 240punycode.<span class="hljs-title function_">toUnicode</span>(<span class="hljs-string">'xn----dqo34k.com'</span>); <span class="hljs-comment">// '☃-⌘.com'</span> 241punycode.<span class="hljs-title function_">toUnicode</span>(<span class="hljs-string">'example.com'</span>); <span class="hljs-comment">// 'example.com'</span></code></pre> 242</section><section><h3><code>punycode.ucs2</code><span><a class="mark" href="#punycode_punycode_ucs2" id="punycode_punycode_ucs2">#</a></span></h3> 243<div class="api_metadata"> 244<span>Added in: v0.7.0</span> 245</div> 246<h4><code>punycode.ucs2.decode(string)</code><span><a class="mark" href="#punycode_punycode_ucs2_decode_string" id="punycode_punycode_ucs2_decode_string">#</a></span></h4> 247<div class="api_metadata"> 248<span>Added in: v0.7.0</span> 249</div> 250<ul> 251<li><code>string</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 252</ul> 253<p>The <code>punycode.ucs2.decode()</code> method returns an array containing the numeric 254codepoint values of each Unicode symbol in the string.</p> 255<pre><code class="language-js">punycode.<span class="hljs-property">ucs2</span>.<span class="hljs-title function_">decode</span>(<span class="hljs-string">'abc'</span>); <span class="hljs-comment">// [0x61, 0x62, 0x63]</span> 256<span class="hljs-comment">// surrogate pair for U+1D306 tetragram for centre:</span> 257punycode.<span class="hljs-property">ucs2</span>.<span class="hljs-title function_">decode</span>(<span class="hljs-string">'\uD834\uDF06'</span>); <span class="hljs-comment">// [0x1D306]</span></code></pre> 258<h4><code>punycode.ucs2.encode(codePoints)</code><span><a class="mark" href="#punycode_punycode_ucs2_encode_codepoints" id="punycode_punycode_ucs2_encode_codepoints">#</a></span></h4> 259<div class="api_metadata"> 260<span>Added in: v0.7.0</span> 261</div> 262<ul> 263<li><code>codePoints</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><integer[]></a></li> 264</ul> 265<p>The <code>punycode.ucs2.encode()</code> method returns a string based on an array of 266numeric code point values.</p> 267<pre><code class="language-js">punycode.<span class="hljs-property">ucs2</span>.<span class="hljs-title function_">encode</span>([<span class="hljs-number">0x61</span>, <span class="hljs-number">0x62</span>, <span class="hljs-number">0x63</span>]); <span class="hljs-comment">// 'abc'</span> 268punycode.<span class="hljs-property">ucs2</span>.<span class="hljs-title function_">encode</span>([<span class="hljs-number">0x1D306</span>]); <span class="hljs-comment">// '\uD834\uDF06'</span></code></pre> 269</section><section><h3><code>punycode.version</code><span><a class="mark" href="#punycode_punycode_version" id="punycode_punycode_version">#</a></span></h3> 270<div class="api_metadata"> 271<span>Added in: v0.6.1</span> 272</div> 273<ul> 274<li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 275</ul> 276<p>Returns a string identifying the current <a href="https://github.com/bestiejs/punycode.js">Punycode.js</a> version number.</p></section> 277 <!-- API END --> 278 </div> 279 </div> 280 </div> 281 <script> 282 'use strict'; 283 { 284 const kCustomPreference = 'customDarkTheme'; 285 const userSettings = sessionStorage.getItem(kCustomPreference); 286 const themeToggleButton = document.getElementById('theme-toggle-btn'); 287 if (userSettings === null && window.matchMedia) { 288 const mq = window.matchMedia('(prefers-color-scheme: dark)'); 289 if ('onchange' in mq) { 290 function mqChangeListener(e) { 291 document.body.classList.toggle('dark-mode', e.matches); 292 } 293 mq.addEventListener('change', mqChangeListener); 294 if (themeToggleButton) { 295 themeToggleButton.addEventListener('click', function() { 296 mq.removeEventListener('change', mqChangeListener); 297 }, { once: true }); 298 } 299 } 300 if (mq.matches) { 301 document.body.classList.add('dark-mode'); 302 } 303 } else if (userSettings === 'true') { 304 document.body.classList.add('dark-mode'); 305 } 306 if (themeToggleButton) { 307 themeToggleButton.hidden = false; 308 themeToggleButton.addEventListener('click', function() { 309 sessionStorage.setItem( 310 kCustomPreference, 311 document.body.classList.toggle('dark-mode') 312 ); 313 }); 314 } 315 } 316 </script> 317</body> 318</html> 319