From 33058f2b292b3a581333bdfb21b8f671898c5060 Mon Sep 17 00:00:00 2001
From: Peter Bengtsson <mail@peterbe.com>
Date: Tue, 8 Dec 2020 14:40:17 -0500
Subject: initial commit

---
 .../atomics/compareexchange/index.html             | 86 ++++++++++++++++++++++
 1 file changed, 86 insertions(+)
 create mode 100644 files/zh-cn/web/javascript/reference/global_objects/atomics/compareexchange/index.html

(limited to 'files/zh-cn/web/javascript/reference/global_objects/atomics/compareexchange')

diff --git a/files/zh-cn/web/javascript/reference/global_objects/atomics/compareexchange/index.html b/files/zh-cn/web/javascript/reference/global_objects/atomics/compareexchange/index.html
new file mode 100644
index 0000000000..1883180411
--- /dev/null
+++ b/files/zh-cn/web/javascript/reference/global_objects/atomics/compareexchange/index.html
@@ -0,0 +1,86 @@
+---
+title: Atomics.compareExchange()
+slug: Web/JavaScript/Reference/Global_Objects/Atomics/compareExchange
+tags:
+  - Atomics
+  - JavaScript
+  - 共享内存
+  - 方法
+translation_of: Web/JavaScript/Reference/Global_Objects/Atomics/compareExchange
+---
+<div>{{JSRef}} {{SeeCompatTable}}</div>
+
+<p><code><strong>Atomics</strong></code><strong><code>.compareExchange()</code></strong> 静态方法会在数组的值与期望值相等的时候，将给定的替换值替换掉数组上的值，然后返回旧值。此原子操作保证在写上修改的值之前不会发生其他写操作。</p>
+
+<div>{{EmbedInteractiveExample("pages/js/atomics-compareexchange.html")}}</div>
+
+
+
+<h2 id="语法">语法</h2>
+
+<pre class="syntaxbox">Atomics.compareExchange(typedArray, index, expectedValue, replacementValue)
+</pre>
+
+<h3 id="参数">参数</h3>
+
+<dl>
+ <dt><code>typedArray</code></dt>
+ <dd>一个共享的整型 typed array。例如 {{jsxref("Int8Array")}}，{{jsxref("Uint8Array")}}，{{jsxref("Int16Array")}}，{{jsxref("Uint16Array")}}，{{jsxref("Int32Array")}}，或 {{jsxref("Uint32Array")}}。</dd>
+ <dt><code>index</code></dt>
+ <dd><code>typedArray</code> 的索引。</dd>
+ <dt><code>expectedValue</code></dt>
+ <dd>用于比较的值。</dd>
+ <dt>replacementValue</dt>
+ <dd>将要替换上的值。</dd>
+</dl>
+
+<h3 id="返回值">返回值</h3>
+
+<p>给定位置的旧值(<code>typedArray[index]</code>).</p>
+
+<h3 id="错误">错误</h3>
+
+<ul>
+ <li>假如 <code>typedArray</code> 不是允许的整型之一，则抛出 {{jsxref("TypeError")}}。</li>
+ <li><code><font face="Open Sans, Arial, sans-serif">假如 </font>typedArray</code> 不是一个贡献的 typed array，则抛出 {{jsxref("TypeError")}}。</li>
+ <li>如果 <code>index</code> 超出了 <code>typedArray 的边界，则抛出</code> {{jsxref("RangeError")}}。</li>
+</ul>
+
+<h2 id="示例">示例</h2>
+
+<pre class="brush: js">var sab = new SharedArrayBuffer(1024);
+var ta = new Uint8Array(sab);
+ta[0] = 7;
+
+Atomics.compareExchange(ta, 0, 7, 12); // returns 7, the old value
+Atomics.load(ta, 0); // 12</pre>
+
+<h2 id="规范">规范</h2>
+
+<table class="standard-table">
+ <tbody>
+  <tr>
+   <th scope="col">Specification</th>
+   <th scope="col">Status</th>
+   <th scope="col">Comment</th>
+  </tr>
+  <tr>
+   <td>{{SpecName('Shared Memory', '#Atomics.compareExchange', 'Atomics.compareExchange')}}</td>
+   <td>{{Spec2('Shared Memory')}}</td>
+   <td>Initial definition.</td>
+  </tr>
+ </tbody>
+</table>
+
+<h2 id="浏览器支持">浏览器支持</h2>
+
+
+
+<p>{{Compat("javascript.builtins.Atomics.compareExchange")}}</p>
+
+<h2 id="相关">相关</h2>
+
+<ul>
+ <li>{{jsxref("Atomics")}}</li>
+ <li>{{jsxref("Atomics.exchange()")}}</li>
+</ul>
-- 
cgit v1.2.3-54-g00ecf