2018-10-10 18:03:03 -04:00
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---
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id: 587d7b8a367417b2b2512b4e
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2020-12-16 00:37:30 -07:00
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title: 使用模板字面量创建字符串
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2018-10-10 18:03:03 -04:00
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challengeType: 1
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2020-08-04 15:13:35 +08:00
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forumTopicId: 301200
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2021-01-13 03:31:00 +01:00
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dashedName: create-strings-using-template-literals
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2018-10-10 18:03:03 -04:00
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---
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2020-12-16 00:37:30 -07:00
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# --description--
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2020-08-04 15:13:35 +08:00
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模板字符串是 ES6 的另外一项新的功能。这是一种可以轻松构建复杂字符串的方法。
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2020-12-16 00:37:30 -07:00
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2020-08-04 15:13:35 +08:00
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模板字符串可以使用多行字符串和字符串插值功能。
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2020-12-16 00:37:30 -07:00
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2020-08-04 15:13:35 +08:00
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请看以下代码:
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```js
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const person = {
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name: "Zodiac Hasbro",
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age: 56
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};
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// Template literal with multi-line and string interpolation
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const greeting = `Hello, my name is ${person.name}!
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I am ${person.age} years old.`;
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console.log(greeting); // prints
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// Hello, my name is Zodiac Hasbro!
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// I am 56 years old.
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```
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2020-12-16 00:37:30 -07:00
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这段代码有许多的不同: 首先,上面的例子使用了反引号(`` ` ``)而不是引号(`'` 或者 `"`)定义字符串。 其次,注意字符串是多行的,不管是代码还是输出。这是因为在字符串内插入了 `\n`。 上面使用的`${variable}`语法是一个占位符。这样一来,你将不再需要使用`+`运算符来连接字符串。当需要在字符串里增加变量的时候,你只需要在变量的外面括上`${`和`}`,并将其放在字符串里就可以了。 这个新的方式使你可以更灵活的创建复杂的字符串。
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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# --instructions--
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使用模板字符串的反引号的语法来展示`result`对象的`failure`数组内的每个条目。每个条目应该括在带有`text-warning`类属性的`li`标签中,并赋值给`resultDisplayArray`。
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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使用遍历方法(可以是任意形式的循环)输出指定值。
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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# --hints--
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2018-10-10 18:03:03 -04:00
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`resultDisplayArray` 是一个包含了 `result failure` 内的消息的数组。
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2018-10-10 18:03:03 -04:00
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```js
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assert(
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typeof makeList(result.failure) === 'object' &&
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resultDisplayArray.length === 3
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);
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2018-10-10 18:03:03 -04:00
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```
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2020-12-16 00:37:30 -07:00
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`resultDisplayArray` 要有正确的输出。
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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```js
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assert(
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makeList(result.failure).every(
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(v, i) =>
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v === `<li class="text-warning">${result.failure[i]}</li>` ||
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v === `<li class='text-warning'>${result.failure[i]}</li>`
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)
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);
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```
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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应使用模板字符串。
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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```js
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(getUserInput) => assert(getUserInput('index').match(/(`.*\${.*}.*`)/));
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```
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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应该遍历。
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2018-10-10 18:03:03 -04:00
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```js
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2020-12-16 00:37:30 -07:00
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(getUserInput) =>
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assert(getUserInput('index').match(/for|map|reduce|forEach|while/));
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2018-10-10 18:03:03 -04:00
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```
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2020-08-04 15:13:35 +08:00
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2021-01-13 03:31:00 +01:00
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# --seed--
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## --seed-contents--
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```js
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const result = {
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success: ["max-length", "no-amd", "prefer-arrow-functions"],
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failure: ["no-var", "var-on-top", "linebreak"],
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skipped: ["no-extra-semi", "no-dup-keys"]
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};
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function makeList(arr) {
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// Only change code below this line
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const failureItems = [];
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// Only change code above this line
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return failureItems;
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}
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const failuresList = makeList(result.failure);
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```
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2020-12-16 00:37:30 -07:00
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# --solutions--
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2021-01-13 03:31:00 +01:00
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```js
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const result = {
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success: ["max-length", "no-amd", "prefer-arrow-functions"],
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failure: ["no-var", "var-on-top", "linebreak"],
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skipped: ["no-extra-semi", "no-dup-keys"]
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};
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function makeList(arr) {
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return arr.map(val => `<li class="text-warning">${val}</li>`);
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}
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const failuresList = makeList(result.failure);
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```
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