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>
116 lines
2.6 KiB
Markdown
116 lines
2.6 KiB
Markdown
---
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id: 56533eb9ac21ba0edf2244bd
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title: 将值传递给带有参数的函数
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challengeType: 1
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videoUrl: 'https://scrimba.com/c/cy8rahW'
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forumTopicId: 18254
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dashedName: passing-values-to-functions-with-arguments
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---
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# --description--
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函数的参数`parameters`在函数中充当占位符(也叫形参)的作用，参数可以为一个或多个。调用一个函数时所传入的参数为实参，实参决定着形参真正的值。简单理解：形参即形式、实参即内容。
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这是带有两个参数的函数，`param1`和`param2`：
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```js
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function testFun(param1, param2) {
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console.log(param1, param2);
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}
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```
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接着我们调用`testFun`： `testFun("Hello", "World");` 我们传递了两个参数，`"Hello"`和`"World"`。在函数内部，`param1`等于“Hello”，`param2`等于“World”。请注意，`testFun`函数可以多次调用，每次调用时传递的参数会决定形参的实际值。
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# --instructions--
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<ol><li>创建一个名为<code>functionWithArgs</code>的函数，它可以接收两个参数，计算参数的和，将结果输出到控制台。</li><li>调用这个函数。</li></ol>
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# --hints--
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`functionWithArgs`应该是一个函数。
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```js
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assert(typeof functionWithArgs === 'function');
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```
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`functionWithArgs(1,2)`应该输出`3`。
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```js
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if (typeof functionWithArgs === 'function') {
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capture();
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functionWithArgs(1, 2);
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uncapture();
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}
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assert(logOutput == 3);
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```
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`functionWithArgs(7,9)`应该输出`16`。
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```js
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if (typeof functionWithArgs === 'function') {
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capture();
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functionWithArgs(7, 9);
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uncapture();
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}
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assert(logOutput == 16);
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```
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在你定义`functionWithArgs`之后记得调用它。
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```js
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assert(/^\s*functionWithArgs\s*\(\s*\d+\s*,\s*\d+\s*\)\s*;?/m.test(code));
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```
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# --seed--
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## --before-user-code--
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```js
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var logOutput = "";
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var originalConsole = console
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function capture() {
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var nativeLog = console.log;
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console.log = function (message) {
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if(message) logOutput = JSON.stringify(message).trim();
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if(nativeLog.apply) {
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nativeLog.apply(originalConsole, arguments);
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} else {
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var nativeMsg = Array.prototype.slice.apply(arguments).join(' ');
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nativeLog(nativeMsg);
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}
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};
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}
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function uncapture() {
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console.log = originalConsole.log;
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}
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capture();
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```
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## --after-user-code--
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```js
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uncapture();
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if (typeof functionWithArgs !== "function") {
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(function() { return "functionWithArgs is not defined"; })();
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} else {
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(function() { return logOutput || "console.log never called"; })();
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}
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```
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## --seed-contents--
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```js
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```
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# --solutions--
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```js
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function functionWithArgs(a, b) {
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console.log(a + b);
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}
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functionWithArgs(10, 5);
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```
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