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<div id="column1" data-id="querystring" 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 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href="https://nodejs.org/docs/latest-v15.x/api/querystring.html">15.x</a></li> 123<li><a href="https://nodejs.org/docs/latest-v14.x/api/querystring.html">14.x <b>LTS</b></a></li> 124<li><a href="https://nodejs.org/docs/latest-v13.x/api/querystring.html">13.x</a></li> 125<li><a href="https://nodejs.org/docs/latest-v12.x/api/querystring.html">12.x <b>LTS</b></a></li> 126<li><a href="https://nodejs.org/docs/latest-v11.x/api/querystring.html">11.x</a></li> 127<li><a href="https://nodejs.org/docs/latest-v10.x/api/querystring.html">10.x</a></li> 128<li><a href="https://nodejs.org/docs/latest-v9.x/api/querystring.html">9.x</a></li> 129<li><a href="https://nodejs.org/docs/latest-v8.x/api/querystring.html">8.x</a></li> 130<li><a href="https://nodejs.org/docs/latest-v7.x/api/querystring.html">7.x</a></li> 131<li><a href="https://nodejs.org/docs/latest-v6.x/api/querystring.html">6.x</a></li> 132<li><a href="https://nodejs.org/docs/latest-v5.x/api/querystring.html">5.x</a></li> 133<li><a href="https://nodejs.org/docs/latest-v4.x/api/querystring.html">4.x</a></li> 134<li><a href="https://nodejs.org/docs/latest-v0.12.x/api/querystring.html">0.12.x</a></li> 135<li><a href="https://nodejs.org/docs/latest-v0.10.x/api/querystring.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/querystring.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_3"><a href="#querystring_query_string">Query string</a></span> 146<ul> 147<li><a href="#querystring_querystring_decode"><code>querystring.decode()</code></a></li> 148<li><a href="#querystring_querystring_encode"><code>querystring.encode()</code></a></li> 149<li><a href="#querystring_querystring_escape_str"><code>querystring.escape(str)</code></a></li> 150<li><a href="#querystring_querystring_parse_str_sep_eq_options"><code>querystring.parse(str[, sep[, eq[, options]]])</code></a></li> 151<li><a href="#querystring_querystring_stringify_obj_sep_eq_options"><code>querystring.stringify(obj[, sep[, eq[, options]]])</code></a></li> 152<li><a href="#querystring_querystring_unescape_str"><code>querystring.unescape(str)</code></a></li> 153</ul> 154</li> 155</ul></details> 156 157 <div id="apicontent"> 158 <h2>Query string<span><a class="mark" href="#querystring_query_string" id="querystring_query_string">#</a></span></h2> 159 160<p></p><div class="api_stability api_stability_3"><a href="documentation.html#documentation_stability_index">Stability: 3</a> - Legacy</div><p></p> 161 162<p><strong>Source Code:</strong> <a href="https://github.com/nodejs/node/blob/v14.20.1/lib/querystring.js">lib/querystring.js</a></p> 163<p>The <code>querystring</code> module provides utilities for parsing and formatting URL 164query strings. It can be accessed using:</p> 165<pre><code class="language-js"><span class="hljs-keyword">const</span> querystring = <span class="hljs-built_in">require</span>(<span class="hljs-string">'querystring'</span>);</code></pre> 166<p>The <code>querystring</code> API is considered Legacy. While it is still maintained, 167new code should use the <a href="url.html#url_class_urlsearchparams" class="type"><URLSearchParams></a> API instead.</p> 168<section><h3><code>querystring.decode()</code><span><a class="mark" href="#querystring_querystring_decode" id="querystring_querystring_decode">#</a></span></h3> 169<div class="api_metadata"> 170<span>Added in: v0.1.99</span> 171</div> 172<p>The <code>querystring.decode()</code> function is an alias for <code>querystring.parse()</code>.</p> 173</section><section><h3><code>querystring.encode()</code><span><a class="mark" href="#querystring_querystring_encode" id="querystring_querystring_encode">#</a></span></h3> 174<div class="api_metadata"> 175<span>Added in: v0.1.99</span> 176</div> 177<p>The <code>querystring.encode()</code> function is an alias for <code>querystring.stringify()</code>.</p> 178</section><section><h3><code>querystring.escape(str)</code><span><a class="mark" href="#querystring_querystring_escape_str" id="querystring_querystring_escape_str">#</a></span></h3> 179<div class="api_metadata"> 180<span>Added in: v0.1.25</span> 181</div> 182<ul> 183<li><code>str</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 184</ul> 185<p>The <code>querystring.escape()</code> method performs URL percent-encoding on the given 186<code>str</code> in a manner that is optimized for the specific requirements of URL 187query strings.</p> 188<p>The <code>querystring.escape()</code> method is used by <code>querystring.stringify()</code> and is 189generally not expected to be used directly. It is exported primarily to allow 190application code to provide a replacement percent-encoding implementation if 191necessary by assigning <code>querystring.escape</code> to an alternative function.</p> 192</section><section><h3><code>querystring.parse(str[, sep[, eq[, options]]])</code><span><a class="mark" href="#querystring_querystring_parse_str_sep_eq_options" id="querystring_querystring_parse_str_sep_eq_options">#</a></span></h3> 193<div class="api_metadata"> 194<details class="changelog"><summary>History</summary> 195<table> 196<tbody><tr><th>Version</th><th>Changes</th></tr> 197<tr><td>v8.0.0</td> 198<td><p>Multiple empty entries are now parsed correctly (e.g. <code>&=&=</code>).</p></td></tr> 199<tr><td>v6.0.0</td> 200<td><p>The returned object no longer inherits from <code>Object.prototype</code>.</p></td></tr> 201<tr><td>v6.0.0, v4.2.4</td> 202<td><p>The <code>eq</code> parameter may now have a length of more than <code>1</code>.</p></td></tr> 203<tr><td>v0.1.25</td> 204<td><p><span>Added in: v0.1.25</span></p></td></tr> 205</tbody></table> 206</details> 207</div> 208<ul> 209<li><code>str</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The URL query string to parse</li> 210<li><code>sep</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The substring used to delimit key and value pairs in the 211query string. <strong>Default:</strong> <code>'&'</code>.</li> 212<li><code>eq</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a>. The substring used to delimit keys and values in the 213query string. <strong>Default:</strong> <code>'='</code>.</li> 214<li><code>options</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> 215<ul> 216<li><code>decodeURIComponent</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a> The function to use when decoding 217percent-encoded characters in the query string. <strong>Default:</strong> 218<code>querystring.unescape()</code>.</li> 219<li><code>maxKeys</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> Specifies the maximum number of keys to parse. 220Specify <code>0</code> to remove key counting limitations. <strong>Default:</strong> <code>1000</code>.</li> 221</ul> 222</li> 223</ul> 224<p>The <code>querystring.parse()</code> method parses a URL query string (<code>str</code>) into a 225collection of key and value pairs.</p> 226<p>For example, the query string <code>'foo=bar&abc=xyz&abc=123'</code> is parsed into:</p> 227<!-- eslint-skip --> 228<pre><code class="language-js">{ 229 <span class="hljs-attr">foo</span>: <span class="hljs-string">'bar'</span>, 230 <span class="hljs-attr">abc</span>: [<span class="hljs-string">'xyz'</span>, <span class="hljs-string">'123'</span>] 231}</code></pre> 232<p>The object returned by the <code>querystring.parse()</code> method <em>does not</em> 233prototypically inherit from the JavaScript <code>Object</code>. This means that typical 234<code>Object</code> methods such as <code>obj.toString()</code>, <code>obj.hasOwnProperty()</code>, and others 235are not defined and <em>will not work</em>.</p> 236<p>By default, percent-encoded characters within the query string will be assumed 237to use UTF-8 encoding. If an alternative character encoding is used, then an 238alternative <code>decodeURIComponent</code> option will need to be specified:</p> 239<pre><code class="language-js"><span class="hljs-comment">// Assuming gbkDecodeURIComponent function already exists...</span> 240 241querystring.<span class="hljs-title function_">parse</span>(<span class="hljs-string">'w=%D6%D0%CE%C4&foo=bar'</span>, <span class="hljs-literal">null</span>, <span class="hljs-literal">null</span>, 242 { <span class="hljs-attr">decodeURIComponent</span>: gbkDecodeURIComponent });</code></pre> 243</section><section><h3><code>querystring.stringify(obj[, sep[, eq[, options]]])</code><span><a class="mark" href="#querystring_querystring_stringify_obj_sep_eq_options" id="querystring_querystring_stringify_obj_sep_eq_options">#</a></span></h3> 244<div class="api_metadata"> 245<span>Added in: v0.1.25</span> 246</div> 247<ul> 248<li><code>obj</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> The object to serialize into a URL query string</li> 249<li><code>sep</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The substring used to delimit key and value pairs in the 250query string. <strong>Default:</strong> <code>'&'</code>.</li> 251<li><code>eq</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a>. The substring used to delimit keys and values in the 252query string. <strong>Default:</strong> <code>'='</code>.</li> 253<li><code>options</code> 254<ul> 255<li><code>encodeURIComponent</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a> The function to use when converting 256URL-unsafe characters to percent-encoding in the query string. <strong>Default:</strong> 257<code>querystring.escape()</code>.</li> 258</ul> 259</li> 260</ul> 261<p>The <code>querystring.stringify()</code> method produces a URL query string from a 262given <code>obj</code> by iterating through the object's "own properties".</p> 263<p>It serializes the following types of values passed in <code>obj</code>: 264<a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/BigInt" class="type"><bigint></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string[]></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number[]></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/BigInt" class="type"><bigint[]></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean[]></a> 265The numeric values must be finite. Any other input values will be coerced to 266empty strings.</p> 267<pre><code class="language-js">querystring.<span class="hljs-title function_">stringify</span>({ <span class="hljs-attr">foo</span>: <span class="hljs-string">'bar'</span>, <span class="hljs-attr">baz</span>: [<span class="hljs-string">'qux'</span>, <span class="hljs-string">'quux'</span>], <span class="hljs-attr">corge</span>: <span class="hljs-string">''</span> }); 268<span class="hljs-comment">// Returns 'foo=bar&baz=qux&baz=quux&corge='</span> 269 270querystring.<span class="hljs-title function_">stringify</span>({ <span class="hljs-attr">foo</span>: <span class="hljs-string">'bar'</span>, <span class="hljs-attr">baz</span>: <span class="hljs-string">'qux'</span> }, <span class="hljs-string">';'</span>, <span class="hljs-string">':'</span>); 271<span class="hljs-comment">// Returns 'foo:bar;baz:qux'</span></code></pre> 272<p>By default, characters requiring percent-encoding within the query string will 273be encoded as UTF-8. If an alternative encoding is required, then an alternative 274<code>encodeURIComponent</code> option will need to be specified:</p> 275<pre><code class="language-js"><span class="hljs-comment">// Assuming gbkEncodeURIComponent function already exists,</span> 276 277querystring.<span class="hljs-title function_">stringify</span>({ <span class="hljs-attr">w</span>: <span class="hljs-string">'中文'</span>, <span class="hljs-attr">foo</span>: <span class="hljs-string">'bar'</span> }, <span class="hljs-literal">null</span>, <span class="hljs-literal">null</span>, 278 { <span class="hljs-attr">encodeURIComponent</span>: gbkEncodeURIComponent });</code></pre> 279</section><section><h3><code>querystring.unescape(str)</code><span><a class="mark" href="#querystring_querystring_unescape_str" id="querystring_querystring_unescape_str">#</a></span></h3> 280<div class="api_metadata"> 281<span>Added in: v0.1.25</span> 282</div> 283<ul> 284<li><code>str</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 285</ul> 286<p>The <code>querystring.unescape()</code> method performs decoding of URL percent-encoded 287characters on the given <code>str</code>.</p> 288<p>The <code>querystring.unescape()</code> method is used by <code>querystring.parse()</code> and is 289generally not expected to be used directly. It is exported primarily to allow 290application code to provide a replacement decoding implementation if 291necessary by assigning <code>querystring.unescape</code> to an alternative function.</p> 292<p>By default, the <code>querystring.unescape()</code> method will attempt to use the 293JavaScript built-in <code>decodeURIComponent()</code> method to decode. If that fails, 294a safer equivalent that does not throw on malformed URLs will be used.</p></section> 295 <!-- API END --> 296 </div> 297 </div> 298 </div> 299 <script> 300 'use strict'; 301 { 302 const kCustomPreference = 'customDarkTheme'; 303 const userSettings = sessionStorage.getItem(kCustomPreference); 304 const themeToggleButton = document.getElementById('theme-toggle-btn'); 305 if (userSettings === null && window.matchMedia) { 306 const mq = window.matchMedia('(prefers-color-scheme: dark)'); 307 if ('onchange' in mq) { 308 function mqChangeListener(e) { 309 document.body.classList.toggle('dark-mode', e.matches); 310 } 311 mq.addEventListener('change', mqChangeListener); 312 if (themeToggleButton) { 313 themeToggleButton.addEventListener('click', function() { 314 mq.removeEventListener('change', mqChangeListener); 315 }, { once: true }); 316 } 317 } 318 if (mq.matches) { 319 document.body.classList.add('dark-mode'); 320 } 321 } else if (userSettings === 'true') { 322 document.body.classList.add('dark-mode'); 323 } 324 if (themeToggleButton) { 325 themeToggleButton.hidden = false; 326 themeToggleButton.addEventListener('click', function() { 327 sessionStorage.setItem( 328 kCustomPreference, 329 document.body.classList.toggle('dark-mode') 330 ); 331 }); 332 } 333 } 334 </script> 335</body> 336</html> 337