ee1e8abd87
* feat(tools): add seed/solution restore script * chore(curriculum): remove empty sections' markers * chore(curriculum): add seed + solution to Chinese * chore: remove old formatter * fix: update getChallenges parse translated challenges separately, without reference to the source * chore(curriculum): add dashedName to English * chore(curriculum): add dashedName to Chinese * refactor: remove unused challenge property 'name' * fix: relax dashedName requirement * fix: stray tag Remove stray `pre` tag from challenge file. Signed-off-by: nhcarrigan <nhcarrigan@gmail.com> Co-authored-by: nhcarrigan <nhcarrigan@gmail.com>
129 lines
2.2 KiB
Markdown
129 lines
2.2 KiB
Markdown
---
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id: 56533eb9ac21ba0edf2244de
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title: 在 Switch 语句中添加默认选项
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challengeType: 1
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videoUrl: 'https://scrimba.com/c/c3JvVfg'
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forumTopicId: 16653
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dashedName: adding-a-default-option-in-switch-statements
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---
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# --description--
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在`switch`语句中你可能无法用 case 来指定所有情况，这时你可以添加 default 语句。当再也找不到 case 匹配的时候 default 语句会执行，非常类似于 if/else 组合中的 else 语句。
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`default`语句应该是最后一个 case。
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```js
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switch (num) {
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case value1:
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statement1;
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break;
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case value2:
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statement2;
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break;
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...
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default:
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defaultStatement;
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break;
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}
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```
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# --instructions--
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写一个 switch 语句，根据下面的条件来设置`answer`的switch语句：
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`"a"` - "apple"
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`"b"` - "bird"
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`"c"` - "cat"
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`default` - "stuff"
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# --hints--
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`switchOfStuff("a")`应该有一个值为 "apple"。
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```js
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assert(switchOfStuff('a') === 'apple');
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```
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`switchOfStuff("b")`应该有一个值为 "bird"。
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```js
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assert(switchOfStuff('b') === 'bird');
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```
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`switchOfStuff("c")`应该有一个值为 "cat"。
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```js
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assert(switchOfStuff('c') === 'cat');
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```
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`switchOfStuff("d")`应该有一个值为 "stuff"。
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```js
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assert(switchOfStuff('d') === 'stuff');
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```
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`switchOfStuff(4)`应该有一个值为 "stuff"。
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```js
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assert(switchOfStuff(4) === 'stuff');
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```
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不能使用任何`if`或`else`表达式。
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```js
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assert(!/else/g.test(code) || !/if/g.test(code));
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```
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你应该有一个`default`表达式。
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```js
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assert(switchOfStuff('string-to-trigger-default-case') === 'stuff');
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```
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你应该有至少 3 个`break`表达式。
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```js
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assert(code.match(/break/g).length > 2);
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```
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# --seed--
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## --seed-contents--
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```js
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function switchOfStuff(val) {
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var answer = "";
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// Only change code below this line
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// Only change code above this line
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return answer;
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}
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switchOfStuff(1);
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```
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# --solutions--
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```js
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function switchOfStuff(val) {
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var answer = "";
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switch(val) {
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case "a":
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answer = "apple";
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break;
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case "b":
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answer = "bird";
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break;
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case "c":
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answer = "cat";
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break;
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default:
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answer = "stuff";
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}
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return answer;
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}
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```
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