JavaScript Map keys() Method

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for (const x of fruits.keys()) { text += x; } </pre> <p class="tiy"><a target="_blank" href="/ha/tiy/t.html?f=jsref_map_keys">Gwada shi kai gaba</a></p> <div class="note"> <h3>Kai tsarki a matsayin abin</h3> <p class="note"><span>Kamata:</span>Yana da kai ita juna halittu da Map ita shi ta yiwa kowane abin da ke a cikin ita gaba</p> </div> <h3>Tari 2</h3> <pre class="language-js"> // Ana cikin abin const apples = {name: 'Apples'}; const bananas = {name: 'Bananas'}; const oranges = {name: 'Oranges'}; // Ana cikin Map const fruits = new Map(); // Yaba abin da ke a cikin Map fruits.set(apples, 500); fruits.set(bananas, 300); fruits.set(oranges, 200); </pre> <p class="tiy"><a target="_blank" href="/ha/tiy/t.html?f=jsref_map_create_objects">Gwada shi kai gaba</a></p> <p class="important"><span>Kashe:</span>Kai tsarki ita shi abin da yana cikin (apples), ba saukiya shi ("apples"):</p> <h3>Tari 3</h3> <pre class="language-js"> fruits.get("apples"); // Mai samu undefined </pre> <p class="tiy"><a target="_blank" href="/ha/tiy/t.html?f=jsref_map_get_undefined">Gwada shi kai gaba</a></p> </section> <section> <h2>Lamurin</h2> <pre class="language-js"> map.keys() </pre> <h3>Ajiyi</h3> <p>Ba da ba da.</p> <h3>Mai samu.</h3> <table class="technical-details"> <tr> <th style="width: 25%;">Turi</th> <th>Bayani</th> </tr> <tr> <td>Iterator</td> <td>Kamfanin da kai tsarki kai yana da kowane abin da ke a cikin Map</td> </tr> </table> </section> <section> <h2>Tsarin kewayi na browsers</h2> <p><code>map.keys()</code> Anuwan ECMAScript6 (ES6) ne.</p> <p>Daga 2017 san wata 6 kacce, dukkanin da yau da suka kewayi ES6 (JavaScript 2015):</p> <table class="browser-support"> <tr> <th class="bsChrome">Chrome</th> <th class="bsEdge">Edge</th> <th class="bsFirefox">Firefox</th> <th class="bsSafari">Safari</th> <th class="bsOpera">Opera</th> </tr> <tr> <td>Chrome 51</td> <td>Edge 15</td> <td>Firefox 54</td> <td>Safari 10</td> <td>Opera 38</td> </tr> <tr> <td>2016 san wata 5</td> <td>2017 san wata 4</td> <td>2017 Yuli</td> <td>2016 Ƙarfi</td> <td>2016 Yuli</td> </tr> </table> <p><code>map.keys()</code> Ba ɗanɗi ba ɗanɗiwaɗa ɗanɗiwaɗa. ɗanɗiwaɗa ɗanɗiwaɗa.</p> </section> <section class="related-pages"> <h2>ɗanɗiwaɗa</h2> <p>Tuturu:<a href="/ha/js/js_maps.html" title="">JavaScript Map</a></p> <p>Tuturu:<a href="/ha/js/js_iterables.html" title="">JavaScript ɗanɗiwaɗa</a></p> <p>Manzo:<a href="/ha/jsref/jsref_obj_map.html" title="">JavaScript Map</a></p> </section> <div class="prenextnav-ref"> <ul> <li> Naɗiwaɗa <a href="/ha/jsref/jsref_map_has.html" title="JavaScript Map has() ɗanɗi">has()</a></li> <li> Naɗiwaɗa <a href="/ha/jsref/jsref_map_set.html" title="JavaScript Map set() ɗanɗi">set()</a></li> <li> Naɗɗiwaɗa <a href="/ha/jsref/jsref_obj_map.html" title="Manjo na JavaScript Map">Manjo na JavaScript Map</a></li> </ul> </div><div style="background-color:#fcfdf8; 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