79 lines
1.6 KiB
Markdown
79 lines
1.6 KiB
Markdown
---
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id: 56533eb9ac21ba0edf2244ed
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title: 将变量追加到字符串
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challengeType: 1
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videoUrl: 'https://scrimba.com/c/cbQmZfa'
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forumTopicId: 16656
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dashedName: appending-variables-to-strings
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---
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# --description--
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就像我们可以用多行字符串<dfn>字面量</dfn>构建单个字符串一样，我们还可以使用加且赋值（`+=`）运算符将字符串追加到字符串的末尾。
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示例：
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```js
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var anAdjective = "awesome!";
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var ourStr = "freeCodeCamp is ";
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ourStr += anAdjective;
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```
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`ourStr` 值为 `freeCodeCamp is awesome!`。
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# --instructions--
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将 `someAdjective` 设置为一个至少包含 3 个字符的字符串，然后使用 `+=` 运算符将它追加到 `myStr`。
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# --hints--
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`someAdjective` 应当为包含至少三个字符的字符串。
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```js
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assert(typeof someAdjective !== 'undefined' && someAdjective.length > 2);
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```
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你应该使用 `+=` 运算符将 `someAdjective` 追加到 `myStr`。
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```js
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assert(code.match(/myStr\s*\+=\s*someAdjective\s*/).length > 0);
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```
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# --seed--
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## --after-user-code--
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```js
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(function(){
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var output = [];
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if(typeof someAdjective === 'string') {
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output.push('someAdjective = "' + someAdjective + '"');
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} else {
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output.push('someAdjective is not a string');
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}
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if(typeof myStr === 'string') {
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output.push('myStr = "' + myStr + '"');
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} else {
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output.push('myStr is not a string');
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}
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return output.join('\n');
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})();
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```
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## --seed-contents--
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```js
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// Change code below this line
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var someAdjective;
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var myStr = "Learning to code is ";
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```
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# --solutions--
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```js
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var someAdjective = "neat";
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var myStr = "Learning to code is ";
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myStr += someAdjective;
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```
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