aboutsummaryrefslogtreecommitdiff
path: root/files/zh-cn/conflicting/web/javascript/reference/statements/switch/index.html
diff options
context:
space:
mode:
Diffstat (limited to 'files/zh-cn/conflicting/web/javascript/reference/statements/switch/index.html')
-rw-r--r--files/zh-cn/conflicting/web/javascript/reference/statements/switch/index.html120
1 files changed, 120 insertions, 0 deletions
diff --git a/files/zh-cn/conflicting/web/javascript/reference/statements/switch/index.html b/files/zh-cn/conflicting/web/javascript/reference/statements/switch/index.html
new file mode 100644
index 0000000000..12e076166c
--- /dev/null
+++ b/files/zh-cn/conflicting/web/javascript/reference/statements/switch/index.html
@@ -0,0 +1,120 @@
+---
+title: default
+slug: Web/JavaScript/Reference/Statements/default
+tags:
+ - JavaScript
+ - Keyword
+translation_of: Web/JavaScript/Reference/Statements/switch
+translation_of_original: Web/JavaScript/Reference/Statements/default
+---
+<div>{{jsSidebar("Statements")}}</div>
+
+<div></div>
+
+<p><strong>default 关键字</strong>可以在 JavaScript 的两种情况下使用:在 {{jsxref("Statements/switch", "switch")}} ,或 {{jsxref("Statements/export", "export")}} 中。</p>
+
+<h2 id="语法">语法</h2>
+
+<p>在{{jsxref("Statements/switch", "switch")}} 语句中使用:</p>
+
+<pre class="syntaxbox">switch (expression) {
+ case value1:
+ //当表达式的值和value1匹配执行这里的语句
+ [break;]
+ default:
+ //当表达式的值没有匹配,执行这里的语句
+ [break;]
+}</pre>
+
+<p>在{{jsxref("Statements/export", "export")}} 中使用:</p>
+
+<pre class="syntaxbox">export default <em>nameN</em> </pre>
+
+<h2 id="描述">描述</h2>
+
+<p>更多细节,参见</p>
+
+<ul>
+ <li>{{jsxref("Statements/switch", "switch")}} 语句和</li>
+ <li>{{jsxref("Statements/export", "export")}} 语句页面。</li>
+</ul>
+
+<h2 id="示例">示例</h2>
+
+<h3 id="在switch语句中使用default">在<code>switch</code>语句中使用<code>default</code></h3>
+
+<p>在以下示例中,如果<code>expr</code>为“Oranges”或“Apples”,程序将匹配“Oranges”或“Apples”的值并执行相应的声明。在任何其它情况下,<code>default</code>关键字将执行关联的语句。</p>
+
+<pre class="brush: js">switch (expr) {
+ case "Oranges":
+ console.log("Oranges are $0.59 a pound.");
+ break;
+ case "Apples":
+ console.log("Apples are $0.32 a pound.");
+ break;
+ default:
+ console.log("Sorry, we are out of " + expr + ".");
+}</pre>
+
+<h3 id="在export语句中使用default">在<code>export</code>语句中使用<code>default</code></h3>
+
+<p>如果要导出单个值或需要模块的回调值,则可以使用默认导出: </p>
+
+<pre class="brush: js">// module "my-module.js"
+let cube = function cube(x) {
+ return x * x * x;
+}
+export default cube;
+</pre>
+
+<p>然后,在另一个脚本中,默认导出将直接被导入:</p>
+
+<pre class="brush: js">// module "my-module.js"
+import myFunction from 'my-module';
+console.log(myFunction(3)); // 27
+</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('ES6', '#sec-switch-statement', 'switch statement')}}</td>
+ <td>{{Spec2('ES6')}}</td>
+ <td></td>
+ </tr>
+ <tr>
+ <td>{{SpecName('ES6', '#sec-exports', 'Exports')}}</td>
+ <td>{{Spec2('ES6')}}</td>
+ <td></td>
+ </tr>
+ <tr>
+ <td>{{SpecName('ESDraft', '#sec-switch-statement', 'switch statement')}}</td>
+ <td>{{Spec2('ESDraft')}}</td>
+ <td></td>
+ </tr>
+ <tr>
+ <td>{{SpecName('ESDraft', '#sec-exports', 'Exports')}}</td>
+ <td>{{Spec2('ESDraft')}}</td>
+ <td></td>
+ </tr>
+ </tbody>
+</table>
+
+<h2 id="浏览器兼容">浏览器兼容</h2>
+
+<div class="hidden">The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out <a href="https://github.com/mdn/browser-compat-data">https://github.com/mdn/browser-compat-data</a> and send us a pull request.</div>
+
+<p>{{Compat("javascript.statements.default")}}</p>
+
+<h2 id="See_also">See also</h2>
+
+<ul>
+ <li>{{jsxref("Statements/export", "export")}}</li>
+ <li>{{jsxref("Statements/switch", "switch")}}</li>
+</ul>