53 lines
1.5 KiB
Markdown
53 lines
1.5 KiB
Markdown
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---
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title: Use conditional logic with If statements
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localeTitle: 对If语句使用条件逻辑
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---
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## 对If语句使用条件逻辑
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### 问题解释：
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_在函数内部创建一个`if`语句`"Yes, that was true"`如果参数`wasThatTrue`为`true`则返回`"Yes, that was true"` `"No, that was false"`否则返回`"No, that was false"` 。_
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#### 提示1
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您的`if`语句将评估您的`(condition)`是`true`还是`false`并执行（如果它的计算结果为`true` ）后面`{statement}`的`{statement}` 。
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> _现在尝试解决问题_
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#### 提示2
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如果您的`(condition)`求值为`false` ，则不会执行`{statement}` ，函数将返回下一个`return`语句。
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> _现在尝试解决问题_
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## 扰流板警报！
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**提前解决！**
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## 基本代码解决方案
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```javascript
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// Setup
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function trueOrFalse(wasThatTrue) {
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// Only change code below this line.
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if (wasThatTrue)
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{
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return "Yes, that was true";
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}
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return "No, that was false";
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// Only change code above this line.
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}
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```
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### 代码说明
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该函数首先计算`if`条件`(wasThatTrue)`计算结果为`true` 。如果是，则ir返回花括号之间的语句。如果没有，则返回它们之外的下一个`return`语句。
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### 资源
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* [“布尔” - MDN词汇表](https://developer.mozilla.org/en-US/docs/Glossary/Boolean)
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* [“if ... else” - MDN JavaScript参考](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/if…else)
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