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diff --git a/files/zh-tw/web/javascript/reference/global_objects/date/now/index.html b/files/zh-tw/web/javascript/reference/global_objects/date/now/index.html new file mode 100644 index 0000000000..00b4842f0f --- /dev/null +++ b/files/zh-tw/web/javascript/reference/global_objects/date/now/index.html @@ -0,0 +1,123 @@ +--- +title: Date.now() +slug: Web/JavaScript/Reference/Global_Objects/Date/now +tags: + - Date + - JavaScript + - 參考 + - 方法 + - 方法補完 +translation_of: Web/JavaScript/Reference/Global_Objects/Date/now +--- +<div>{{JSRef}}</div> + +<p><strong><code>Date.now()</code></strong> 方法回傳自 1970/01/01 00:00:00 UTC 起經過的毫秒數。</p> + +<h2 id="格式">格式</h2> + +<pre class="syntaxbox"><code>var timeInMs = Date.now();</code></pre> + +<h3 id="回傳值">回傳值</h3> + +<p>一個代表由經 UNIX 紀元起經過的毫秒數值({{jsxref("Number")}})。</p> + +<h2 id="描述">描述</h2> + +<p>由於 <code>now()</code> 是 {{jsxref("Date")}} 的靜態方法,你只能用 <code>Date.now()</code> 的方式呼叫它。</p> + +<h2 id="補完">補完</h2> + +<p>這個函數是 ECMA-262 第 5 版的標準。 對於未更新支援此方法的引擎,可以利用底下的程式補上:</p> + +<pre class="brush: js">if (!Date.now) { + Date.now = function now() { + return new Date().getTime(); + }; +} +</pre> + +<h2 id="規範">規範</h2> + +<table class="standard-table"> + <tbody> + <tr> + <th scope="col">規範</th> + <th scope="col">狀態</th> + <th scope="col">註</th> + </tr> + <tr> + <td>{{SpecName('ES5.1', '#sec-15.9.4.4', 'Date.now')}}</td> + <td>{{Spec2('ES5.1')}}</td> + <td>初始定義,實作在 JavaScript 1.5 。</td> + </tr> + <tr> + <td>{{SpecName('ES6', '#sec-date.now', 'Date.now')}}</td> + <td>{{Spec2('ES6')}}</td> + <td> </td> + </tr> + <tr> + <td>{{SpecName('ESDraft', '#sec-date.now', 'Date.now')}}</td> + <td>{{Spec2('ESDraft')}}</td> + <td> </td> + </tr> + </tbody> +</table> + +<h2 id="瀏覽器相容性">瀏覽器相容性</h2> + +<div>{{CompatibilityTable}}</div> + +<div id="compat-desktop"> +<table class="compat-table"> + <tbody> + <tr> + <th>平台</th> + <th>Chrome</th> + <th>Firefox (Gecko)</th> + <th>Internet Explorer</th> + <th>Opera</th> + <th>Safari</th> + </tr> + <tr> + <td>基本支援</td> + <td>{{CompatChrome("5")}}</td> + <td>{{CompatGeckoDesktop("1.9")}}</td> + <td>{{CompatIE("9")}}</td> + <td>{{CompatOpera("10.50")}}</td> + <td>{{CompatSafari("4")}}</td> + </tr> + </tbody> +</table> +</div> + +<div id="compat-mobile"> +<table class="compat-table"> + <tbody> + <tr> + <th>平台</th> + <th>Android</th> + <th>Chrome for Android</th> + <th>Firefox Mobile (Gecko)</th> + <th>IE Mobile</th> + <th>Opera Mobile</th> + <th>Safari Mobile</th> + </tr> + <tr> + <td>基本支援</td> + <td>{{CompatVersionUnknown}}</td> + <td>{{CompatVersionUnknown}}</td> + <td>{{CompatVersionUnknown}}</td> + <td>{{CompatVersionUnknown}}</td> + <td>{{CompatVersionUnknown}}</td> + <td>{{CompatVersionUnknown}}</td> + </tr> + </tbody> +</table> +</div> + +<h2 id="相關資源">相關資源</h2> + +<ul> + <li>{{domxref("Performance.now()")}} — 提供亞毫秒級的時間戳記,作為評估網頁效能的解決方案。</li> + <li>{{domxref("console.time()")}} / {{domxref("console.timeEnd()")}}</li> +</ul> |
