37 lines
796 B
Markdown
37 lines
796 B
Markdown
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---
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title: Conditional Ternary Operators
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localeTitle: 条件三元运算符
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---
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## 条件三元运算符
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### 基本用法
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三元运算符是在表达式中编写if-else的紧凑方法。
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```js
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const thing = (condition) ? <if true> : <if false>;
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```
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例如
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```js
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const cappedInput = input > 50 ? 50 : input // this will cap the input at 50
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```
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### 否则，如果
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你也可以链接三元运算符，这样你就会有一个if-else if-else行为
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```js
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<first condition> ? <value if first true>
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: <second condition> ? <value if second is true>
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: <fallback value>
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```
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> **专业提示** ：如您所见，您可以在多行上拆分三元运算符 例如
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```
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const wealth = housesOwned > 3 ? "rich"
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: housesOwned > 1 ? "nothing to complain"
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: "poor"
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```
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