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/> <path d="M6.76 4.84l-1.8-1.79-1.41 1.41 1.79 1.79 1.42-1.41zM4 10.5H1v2h3v-2zm9-9.95h-2V3.5h2V.55zm7.45 3.91l-1.41-1.41-1.79 1.79 1.41 1.41 1.79-1.79zm-3.21 13.7l1.79 1.8 1.41-1.41-1.8-1.79-1.4 1.4zM20 10.5v2h3v-2h-3zm-8-5c-3.31 0-6 2.69-6 6s2.69 6 6 6 6-2.69 6-6-2.69-6-6-6zm-1 16.95h2V19.5h-2v2.95zm-7.45-3.91l1.41 1.41 1.79-1.8-1.41-1.41-1.79 1.8z"/> </svg> </button> </div> <div id="gtoc"> <ul> <li> <a href="index.html">Index</a> </li> <li> <a href="all.html">View on single page</a> </li> <li> <a href="string_decoder.json">View as JSON</a> </li> <li class="version-picker"> <a href="#">View another version <span>▼</span></a> <ol class="version-picker"><li><a href="https://nodejs.org/docs/latest-v17.x/api/string_decoder.html">17.x</a></li> <li><a href="https://nodejs.org/docs/latest-v16.x/api/string_decoder.html">16.x <b>LTS</b></a></li> <li><a href="https://nodejs.org/docs/latest-v15.x/api/string_decoder.html">15.x</a></li> <li><a href="https://nodejs.org/docs/latest-v14.x/api/string_decoder.html">14.x <b>LTS</b></a></li> <li><a href="https://nodejs.org/docs/latest-v13.x/api/string_decoder.html">13.x</a></li> <li><a href="https://nodejs.org/docs/latest-v12.x/api/string_decoder.html">12.x <b>LTS</b></a></li> <li><a href="https://nodejs.org/docs/latest-v11.x/api/string_decoder.html">11.x</a></li> <li><a href="https://nodejs.org/docs/latest-v10.x/api/string_decoder.html">10.x</a></li> <li><a href="https://nodejs.org/docs/latest-v9.x/api/string_decoder.html">9.x</a></li> <li><a href="https://nodejs.org/docs/latest-v8.x/api/string_decoder.html">8.x</a></li> <li><a href="https://nodejs.org/docs/latest-v7.x/api/string_decoder.html">7.x</a></li> <li><a href="https://nodejs.org/docs/latest-v6.x/api/string_decoder.html">6.x</a></li> <li><a href="https://nodejs.org/docs/latest-v5.x/api/string_decoder.html">5.x</a></li> <li><a href="https://nodejs.org/docs/latest-v4.x/api/string_decoder.html">4.x</a></li> <li><a href="https://nodejs.org/docs/latest-v0.12.x/api/string_decoder.html">0.12.x</a></li> <li><a href="https://nodejs.org/docs/latest-v0.10.x/api/string_decoder.html">0.10.x</a></li></ol> </li> <li class="edit_on_github"><a href="https://github.com/nodejs/node/edit/master/doc/api/string_decoder.md">Edit on GitHub</a></li> </ul> </div> <hr> </header> <details id="toc" open><summary>Table of contents</summary><ul> <li><span class="stability_2"><a href="#string-decoder">String decoder</a></span> <ul> <li><a href="#class-stringdecoder">Class: <code>StringDecoder</code></a> <ul> <li><a href="#new-stringdecoderencoding"><code>new StringDecoder([encoding])</code></a></li> <li><a href="#stringdecoderendbuffer"><code>stringDecoder.end([buffer])</code></a></li> <li><a href="#stringdecoderwritebuffer"><code>stringDecoder.write(buffer)</code></a></li> </ul> </li> </ul> </li> </ul></details> <div id="apicontent"> <h2>String decoder<span><a class="mark" href="#string-decoder" id="string-decoder">#</a></span><a aria-hidden="true" class="legacy" id="string_decoder_string_decoder"></a></h2> <p></p><div class="api_stability api_stability_2"><a href="documentation.html#stability-index">Stability: 2</a> - Stable</div><p></p> <p><strong>Source Code:</strong> <a href="https://github.com/nodejs/node/blob/v16.13.2/lib/string_decoder.js">lib/string_decoder.js</a></p> <p>The <code>string_decoder</code> module provides an API for decoding <code>Buffer</code> objects into strings in a manner that preserves encoded multi-byte UTF-8 and UTF-16 characters. It can be accessed using:</p> <pre><code class="language-js"><span class="hljs-keyword">const</span> { <span class="hljs-title class_">StringDecoder</span> } = <span class="hljs-built_in">require</span>(<span class="hljs-string">'string_decoder'</span>);</code></pre> <p>The following example shows the basic use of the <code>StringDecoder</code> class.</p> <pre><code class="language-js"><span class="hljs-keyword">const</span> { <span class="hljs-title class_">StringDecoder</span> } = <span class="hljs-built_in">require</span>(<span class="hljs-string">'string_decoder'</span>); <span class="hljs-keyword">const</span> decoder = <span class="hljs-keyword">new</span> <span class="hljs-title class_">StringDecoder</span>(<span class="hljs-string">'utf8'</span>); <span class="hljs-keyword">const</span> cent = <span class="hljs-title class_">Buffer</span>.<span class="hljs-title function_">from</span>([<span class="hljs-number">0xC2</span>, <span class="hljs-number">0xA2</span>]); <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(decoder.<span class="hljs-title function_">write</span>(cent)); <span class="hljs-keyword">const</span> euro = <span class="hljs-title class_">Buffer</span>.<span class="hljs-title function_">from</span>([<span class="hljs-number">0xE2</span>, <span class="hljs-number">0x82</span>, <span class="hljs-number">0xAC</span>]); <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(decoder.<span class="hljs-title function_">write</span>(euro));</code></pre> <p>When a <code>Buffer</code> instance is written to the <code>StringDecoder</code> instance, an internal buffer is used to ensure that the decoded string does not contain any incomplete multibyte characters. These are held in the buffer until the next call to <code>stringDecoder.write()</code> or until <code>stringDecoder.end()</code> is called.</p> <p>In the following example, the three UTF-8 encoded bytes of the European Euro symbol (<code>€</code>) are written over three separate operations:</p> <pre><code class="language-js"><span class="hljs-keyword">const</span> { <span class="hljs-title class_">StringDecoder</span> } = <span class="hljs-built_in">require</span>(<span class="hljs-string">'string_decoder'</span>); <span class="hljs-keyword">const</span> decoder = <span class="hljs-keyword">new</span> <span class="hljs-title class_">StringDecoder</span>(<span class="hljs-string">'utf8'</span>); decoder.<span class="hljs-title function_">write</span>(<span class="hljs-title class_">Buffer</span>.<span class="hljs-title function_">from</span>([<span class="hljs-number">0xE2</span>])); decoder.<span class="hljs-title function_">write</span>(<span class="hljs-title class_">Buffer</span>.<span class="hljs-title function_">from</span>([<span class="hljs-number">0x82</span>])); <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(decoder.<span class="hljs-title function_">end</span>(<span class="hljs-title class_">Buffer</span>.<span class="hljs-title function_">from</span>([<span class="hljs-number">0xAC</span>])));</code></pre> <section><h3>Class: <code>StringDecoder</code><span><a class="mark" href="#class-stringdecoder" id="class-stringdecoder">#</a></span><a aria-hidden="true" class="legacy" id="string_decoder_class_stringdecoder"></a></h3> <h4><code>new StringDecoder([encoding])</code><span><a class="mark" href="#new-stringdecoderencoding" id="new-stringdecoderencoding">#</a></span><a aria-hidden="true" class="legacy" id="string_decoder_new_stringdecoder_encoding"></a></h4> <div class="api_metadata"> <span>Added in: v0.1.99</span> </div> <ul> <li><code>encoding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The character <a href="buffer.html#buffers-and-character-encodings">encoding</a> the <code>StringDecoder</code> will use. <strong>Default:</strong> <code>'utf8'</code>.</li> </ul> <p>Creates a new <code>StringDecoder</code> instance.</p> <h4><code>stringDecoder.end([buffer])</code><span><a class="mark" href="#stringdecoderendbuffer" id="stringdecoderendbuffer">#</a></span><a aria-hidden="true" class="legacy" id="string_decoder_stringdecoder_end_buffer"></a></h4> <div class="api_metadata"> <span>Added in: v0.9.3</span> </div> <ul> <li><code>buffer</code> <a href="buffer.html#class-buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a> A <code>Buffer</code>, or <code>TypedArray</code>, or <code>DataView</code> containing the bytes to decode.</li> <li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> </ul> <p>Returns any remaining input stored in the internal buffer as a string. Bytes representing incomplete UTF-8 and UTF-16 characters will be replaced with substitution characters appropriate for the character encoding.</p> <p>If the <code>buffer</code> argument is provided, one final call to <code>stringDecoder.write()</code> is performed before returning the remaining input. After <code>end()</code> is called, the <code>stringDecoder</code> object can be reused for new input.</p> <h4><code>stringDecoder.write(buffer)</code><span><a class="mark" href="#stringdecoderwritebuffer" id="stringdecoderwritebuffer">#</a></span><a aria-hidden="true" class="legacy" id="string_decoder_stringdecoder_write_buffer"></a></h4> <div class="api_metadata"> <details class="changelog"><summary>History</summary> <table> <tbody><tr><th>Version</th><th>Changes</th></tr> <tr><td>v8.0.0</td> <td><p>Each invalid character is now replaced by a single replacement character instead of one for each individual byte.</p></td></tr> <tr><td>v0.1.99</td> <td><p><span>Added in: v0.1.99</span></p></td></tr> </tbody></table> </details> </div> <ul> <li><code>buffer</code> <a href="buffer.html#class-buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a> A <code>Buffer</code>, or <code>TypedArray</code>, or <code>DataView</code> containing the bytes to decode.</li> <li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> </ul> <p>Returns a decoded string, ensuring that any incomplete multibyte characters at the end of the <code>Buffer</code>, or <code>TypedArray</code>, or <code>DataView</code> are omitted from the returned string and stored in an internal buffer for the next call to <code>stringDecoder.write()</code> or <code>stringDecoder.end()</code>.</p></section> <!-- API END --> </div> </div> </div> <script> 'use strict'; { const kCustomPreference = 'customDarkTheme'; const userSettings = sessionStorage.getItem(kCustomPreference); const themeToggleButton = document.getElementById('theme-toggle-btn'); if (userSettings === null && window.matchMedia) { const mq = window.matchMedia('(prefers-color-scheme: dark)'); if ('onchange' in mq) { function mqChangeListener(e) { document.body.classList.toggle('dark-mode', e.matches); } mq.addEventListener('change', mqChangeListener); if (themeToggleButton) { themeToggleButton.addEventListener('click', function() { mq.removeEventListener('change', mqChangeListener); }, { once: true }); } } if (mq.matches) { document.body.classList.add('dark-mode'); } } else if (userSettings === 'true') { document.body.classList.add('dark-mode'); } if (themeToggleButton) { themeToggleButton.hidden = false; themeToggleButton.addEventListener('click', function() { sessionStorage.setItem( kCustomPreference, document.body.classList.toggle('dark-mode') ); }); } } </script> </body> </html>
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