51 lines
879 B
Markdown
51 lines
879 B
Markdown
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---
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id: 56533eb9ac21ba0edf2244a9
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title: 使用賦值運算符初始化變量
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challengeType: 1
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videoUrl: 'https://scrimba.com/c/cWJ4Bfb'
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forumTopicId: 301171
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dashedName: initializing-variables-with-the-assignment-operator
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---
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# --description--
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通常在聲明變量的時候會給變量<dfn>初始化</dfn>一個初始值。
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```js
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var myVar = 0;
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```
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創建一個名爲 `myVar` 的變量,並指定其初始值爲 `0`。
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# --instructions--
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通過關鍵字 `var` 定義一個變量 `a`,並且給它一個初始值 `9`。
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# --hints--
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應該初始化 `a` 的值爲 `9`。
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```js
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assert(/var\s+a\s*=\s*9(\s*;?\s*)$/.test(code));
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```
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# --seed--
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## --after-user-code--
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```js
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if(typeof a !== 'undefined') {(function(a){return "a = " + a;})(a);} else { (function() {return 'a is undefined';})(); }
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```
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## --seed-contents--
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```js
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```
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# --solutions--
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```js
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var a = 9;
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```
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