74 lines
1.2 KiB
Markdown
74 lines
1.2 KiB
Markdown
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---
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id: cf1111c1c11feddfaeb1bdef
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title: while 循環
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challengeType: 1
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videoUrl: 'https://scrimba.com/c/c8QbnCM'
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forumTopicId: 18220
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dashedName: iterate-with-javascript-while-loops
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---
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# --description--
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你可以使用循環多次執行相同的代碼。
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我們將學習的第一種類型的循環稱爲 `while` 循環，當 while 指定的條件爲真，循環纔會執行，反之不執行。
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```js
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var ourArray = [];
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var i = 0;
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while(i < 5) {
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ourArray.push(i);
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i++;
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}
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```
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在上面的代碼裏，`while` 循環執行 5 次把 0 到 4 的數字添加到 `ourArray` 數組裏。
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讓我們通過 while 循環將值添加到數組中。
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# --instructions--
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通過一個 `while` 循環，把從 5 到 0（包括 5 和 0） 的值添加到 `myArray` 中。
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# --hints--
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你應該使用 `while` 循環。
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```js
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assert(code.match(/while/g));
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```
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`myArray` 應該等於 `[5,4,3,2,1,0]`。
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```js
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assert.deepEqual(myArray, [5, 4, 3, 2, 1, 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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if(typeof myArray !== "undefined"){(function(){return myArray;})();}
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```
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## --seed-contents--
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```js
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// Setup
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var myArray = [];
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// Only change code below this line
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```
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# --solutions--
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```js
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var myArray = [];
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var i = 5;
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while(i >= 0) {
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myArray.push(i);
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i--;
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}
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```
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