53 lines
1.4 KiB
Markdown
53 lines
1.4 KiB
Markdown
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---
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title: Comparisons with the && (logical AND) operator
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localeTitle: 与&&（逻辑AND）运算符进行比较
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---
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## 与&&（逻辑AND）运算符进行比较
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### 问题解释：
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· _将两个if语句合并为一个语句，如果`val`小于或等于`50`且大于或等于`25` ，则返回`"Yes"` 。否则，将返回`"No"` 。_
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#### 提示1
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逻辑AND（ `&&` ）运算符比较两个语句，并且仅当两者都为真或可以转换为true（真实）时才返回`true` 。
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> _现在尝试解决问题_
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#### 提示2
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请记住，嵌套`if`语句也可以实现这种效果。
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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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function testLogicalAnd(val) {
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// Only change code below this line
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if (val <= 50 && val >= 25) {
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return "Yes";
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}
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// Only change code above this line
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return "No";
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}
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// Change this value to test
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testLogicalAnd(10);
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```
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· [在repl.it上运行代码](https://repl.it/@AdrianSkar/Basic-JS-Comparison-with-the-and-operator)
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### 代码说明
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功能首先评估`if`条件`val <= 50`的计算结果为`true`转换`val`到一个号码，如果有必要，则确实具有相同的`val >=25` ，因为逻辑AND（的`&&` ）算子;如果两者都返回true，则`return "Yes"`语句。
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### 资源
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* [“逻辑运算符” - _MDN JavaScript参考_](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Logical_Operators)
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