96 lines
2.2 KiB
Markdown
96 lines
2.2 KiB
Markdown
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---
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title: Multiple Identical Options in Switch Statements
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localeTitle: 交换机语句中的多个相同选项
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---
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## 交换机语句中的多个相同选项
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### 问题解释
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_如果从switch语句的大小写中省略了break语句，则会执行以下case语句，直到遇到break。如果您有多个具有相同输出的输入，则可以在switch语句中表示它们，如下所示：_
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```javascript
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switch(val) {
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case 1:
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case 2:
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case 3:
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result = "1, 2, or 3";
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break;
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case 4:
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result = "4 alone";
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}
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```
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_1,2和3的情况都会产生相同的结果。_
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_写一个switch语句来设置以下范围的答案：_ `1-3` - “低”
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`4-6` - “中”
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`7-9` - “高”
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_注意： 您需要为范围中的每个数字都有一个case语句。_
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## 扰流板警报！
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**提前解决！**
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## 代码解决方案
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```javascript
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function sequentialSizes(val) {
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var answer = "";
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// Only change code below this line
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switch(val) {
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case 1:
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case 2:
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case 3:
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return "Low";
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break;
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case 4:
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case 5:
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case 6:
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return "Mid";
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break;
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case 7:
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case 8:
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case 9:
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return "High";
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break;
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}
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// Only change code above this line
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return answer;
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}
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// Change this value to test
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sequentialSizes(1);
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```
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## 替代代码解决方案
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```javascript
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function sequentialSizes(val) {
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var answer = "";
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// Only change code below this line
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switch(val){
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case 1: case 2: case 3:
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answer = "Low";
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break;
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case 4: case 5: case 6:
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answer = "Mid";
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break;
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case 7: case 8: case 9:
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answer = "High";
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}
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// Only change code above this line
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return answer;
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}
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// Change this value to test
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sequentialSizes(1);
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```
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·在[repl.it上](https://repl.it/@AdrianSkar/Basic-JS-Multiple-opts-in-switch)运行代码。
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### 代码说明
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由于您已经定义了一个名为`answer`的变量并且函数返回它，因此您可以在每组case语句中修改其值以满足练习要求。
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### 资源
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* [“切换：多标准案例的方法” - _MDN Javascript参考_](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/switch)
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