{ "type": "module", "source": "doc/api/string_decoder.md", "modules": [ { "textRaw": "String Decoder", "name": "string_decoder", "introduced_in": "v0.10.0", "stability": 2, "stabilityText": "Stable", "desc": "<p>The <code>string_decoder</code> module provides an API for decoding <code>Buffer</code> objects into\nstrings in a manner that preserves encoded multi-byte UTF-8 and UTF-16\ncharacters. It can be accessed using:</p>\n<pre><code class=\"language-js\">const { StringDecoder } = require('string_decoder');\n</code></pre>\n<p>The following example shows the basic use of the <code>StringDecoder</code> class.</p>\n<pre><code class=\"language-js\">const { StringDecoder } = require('string_decoder');\nconst decoder = new StringDecoder('utf8');\n\nconst cent = Buffer.from([0xC2, 0xA2]);\nconsole.log(decoder.write(cent));\n\nconst euro = Buffer.from([0xE2, 0x82, 0xAC]);\nconsole.log(decoder.write(euro));\n</code></pre>\n<p>When a <code>Buffer</code> instance is written to the <code>StringDecoder</code> instance, an\ninternal buffer is used to ensure that the decoded string does not contain\nany incomplete multibyte characters. These are held in the buffer until the\nnext call to <code>stringDecoder.write()</code> or until <code>stringDecoder.end()</code> is called.</p>\n<p>In the following example, the three UTF-8 encoded bytes of the European Euro\nsymbol (<code>€</code>) are written over three separate operations:</p>\n<pre><code class=\"language-js\">const { StringDecoder } = require('string_decoder');\nconst decoder = new StringDecoder('utf8');\n\ndecoder.write(Buffer.from([0xE2]));\ndecoder.write(Buffer.from([0x82]));\nconsole.log(decoder.end(Buffer.from([0xAC])));\n</code></pre>", "classes": [ { "textRaw": "Class: StringDecoder", "type": "class", "name": "StringDecoder", "methods": [ { "textRaw": "stringDecoder.end([buffer])", "type": "method", "name": "end", "meta": { "added": [ "v0.9.3" ], "changes": [] }, "signatures": [ { "return": { "textRaw": "Returns: {string}", "name": "return", "type": "string" }, "params": [ { "textRaw": "`buffer` {Buffer|TypedArray|DataView} A `Buffer`, or `TypedArray`, or `DataView` containing the bytes to decode.", "name": "buffer", "type": "Buffer|TypedArray|DataView", "desc": "A `Buffer`, or `TypedArray`, or `DataView` containing the bytes to decode.", "optional": true } ] } ], "desc": "<p>Returns any remaining input stored in the internal buffer as a string. Bytes\nrepresenting incomplete UTF-8 and UTF-16 characters will be replaced with\nsubstitution characters appropriate for the character encoding.</p>\n<p>If the <code>buffer</code> argument is provided, one final call to <code>stringDecoder.write()</code>\nis performed before returning the remaining input.</p>" }, { "textRaw": "stringDecoder.write(buffer)", "type": "method", "name": "write", "meta": { "added": [ "v0.1.99" ], "changes": [ { "version": "v8.0.0", "pr-url": "https://github.com/nodejs/node/pull/9618", "description": "Each invalid character is now replaced by a single replacement character instead of one for each individual byte." } ] }, "signatures": [ { "return": { "textRaw": "Returns: {string}", "name": "return", "type": "string" }, "params": [ { "textRaw": "`buffer` {Buffer|TypedArray|DataView} A `Buffer`, or `TypedArray`, or `DataView` containing the bytes to decode.", "name": "buffer", "type": "Buffer|TypedArray|DataView", "desc": "A `Buffer`, or `TypedArray`, or `DataView` containing the bytes to decode." } ] } ], "desc": "<p>Returns a decoded string, ensuring that any incomplete multibyte characters at\nthe end of the <code>Buffer</code>, or <code>TypedArray</code>, or <code>DataView</code> are omitted from the\nreturned string and stored in an internal buffer for the next call to\n<code>stringDecoder.write()</code> or <code>stringDecoder.end()</code>.</p>" } ], "signatures": [ { "params": [ { "textRaw": "`encoding` {string} The character encoding the `StringDecoder` will use. **Default:** `'utf8'`.", "name": "encoding", "type": "string", "default": "`'utf8'`", "desc": "The character encoding the `StringDecoder` will use.", "optional": true } ], "desc": "<p>Creates a new <code>StringDecoder</code> instance.</p>" } ] } ], "type": "module", "displayName": "String Decoder" } ] }