---
# System prepended metadata

title: "\U0001F3C5 Day 9 - 表達式觀念、Bootstrap 格線系統 3"
tags: [React 直播班 - 2025 冬季班]

---

# 🏅 Day 9 - 表達式觀念、Bootstrap 格線系統 3


請同學先閱讀完 「[JavaScript 表達式觀念及運用 - JS Expression](https://wcc723.github.io/development/2020/09/17/js-expression/)」 這篇文章後再作答。

題目
---
#### 問題一（判斷何者為表達式）：

```js=
if(Ans) {
  console.log("Ans 是表達式");
}
```

請問以下有哪些選項代入 Ans 可以輸出 console.log 不會報錯? 
補充: [真值假值觀念](https://developer.mozilla.org/zh-CN/docs/Glossary/Truthy)

```
1. 2 === 2
2. "string"
3. var a 
4. if(true){let a = 2;}
5. [25, 30] // 純陣列
6. {name: "hexSchool"}  // 純物件
```

#### 問題二（表達式的應用）:
```js=
function hexIsGood() {
  return true;
}
```

以上程式碼為一個「表達式」，請大家到 [MDN](https://developer.mozilla.org/en-US/) 或是透過 Google 搜尋，尋找有哪些程式運作可以插入以上的表達式，仍能正確運行。

舉例（if 判斷式）：
```js=
function hexIsGood() {
  return true;
}
if(hexIsGood()) {console.log("此程式碼可以運作")};
```


Bootstrap 格線系統 - 常見錯誤
---
在運用格線系統 `.row` 時，外層需使用 `.container` 、 `.container-*`，避免產生 x 軸
請將此 [CodePen](https://codepen.io/yen-kg/pen/WNVMYbr) 補上 `.container-*`，並觀察其差異


<!-- 解答一
1, 2, 5, 6
因為它們都是表達式，會回傳結果。
-->

<!-- 解答二
// Ex1: 可以帶入三元運算子
function hexIsGood() {
  return true;
}
console.log(hexIsGood() ? '很棒棒' : '不棒棒');

// Ex2: 可以代入樣板字面值
function hexIsGood() {
  return true;
}
let str = `六角學院很讚: ${ hexIsGood() }`;
console.log(str);

-->

<!-- 
- Bootstrap -
將 ... 改為 .container、.、.container-sm .. 都可以
-->

| 名字         | 連結                                                                         |
| ------------ | ---------------------------------------------------------------------------- |
| Zem          | [CodePen](https://codepen.io/dgldwqlg-the-vuer/pen/raLNPGN)                  |
| Jenna        | [CodePen](https://codepen.io/abiscc14/pen/qENBgQm)                           |
| Eileen       | [CodePen](https://codepen.io/Eileen-io/pen/zxBYego)                          |
| Melanie      | [CodePen](https://codepen.io/pnrcspte-the-animator/pen/NPrWomm)              |
| Nooooora     | [CodePen](https://codepen.io/Nora-Ch/pen/pvboYrb?editors=1111)               |
| 登登登       | [CodePen](https://codepen.io/Duncanin/pen/jErOJpr?editors=1000)              |
| Owen He      | [CodePen](https://codepen.io/owen1120/pen/NPrWmWR?editors=0011)              |
| Marco        | [CodePen](https://codepen.io/MarcoChiu/pen/ogLNOwK)                          |
| cindy        | [CodePen](https://codepen.io/a50134/pen/EayxJeJ?editors=0011)                |
| 7Red         | [CodePen](https://codepen.io/cch2655/pen/raLNgYN)                            |
| 平平         | [CodePen](https://codepen.io/ypinpin/pen/raLNEKz)                            |
| 小懿         | [CodePen](https://codepen.io/YT-the-vuer/pen/emzYwPE?editors=1010)           |
| Chia         | [Codepen](https://codepen.io/Chia-the-encoder/pen/RNRwJzJ)                   |
| An           | [Codepen](https://codepen.io/bzrpsbjq-the-encoder/pen/NPrWQjj?editors=1011)  |
| Hugh         | [Codepen](https://codepen.io/Hugh-Chen/pen/vEGqKJL)                          |
| Percy        | [Codepen](https://codepen.io/Percy-Ku/pen/ZYOEgqq)                           |
| 7lun         | [Codepen](https://codepen.io/mfyvqhsn-the-bold/pen/jErENOp?editors=1010)     |
| Naojun       | [Codepen](https://codepen.io/NAOJUN/pen/pvboXJJ)                             |
| tanuki       | [Codepen](https://codepen.io/tanuki320/pen/OPXPLqB?editors=1011)             |
| andy         | [Codepen](https://codepen.io/ewnblckz-the-styleful/pen/qENEWPa?editors=1011) |
| wind         | [Codepen](https://codepen.io/wind7y/pen/ogLgvVe)                             |
| 老屠         | [Codepen](https://codepen.io/fsgfxvlb-the-selector/pen/wBWvyWX)              |
| 地瓜         | [Codepen](https://codepen.io/ChippyYU/pen/VYjYvRg?editors=1010)              |
| JiaMori      | [Codepen](https://codepen.io/jiamori/pen/azZzvgK?editors=1111)               |
| 星雪糖       | [Codepen](https://codepen.io/vfpofbgm-the-scripter/pen/MYeWxaK?editors=1011) |
| Tetsu        | [Codepen](https://codepen.io/ttgchang/pen/pvbvggr)                           |
| RUDY         | [Codepen](https://codepen.io/Rudy-crw/pen/myEyVxV?editors=1010)              |
| jchunnn      | [Codepen](https://codepen.io/jchunnn/pen/VYjYeNe?editors=1011)               |
| Rogan        | [Codepen](https://codepen.io/RoganHsu/pen/zxBxrVQ?editors=1010)              |
| Tippy        | [Codepen](https://codepen.io/Ektodor-Wang/pen/jErEqPp)                       |
| Vergil       | [CodePen](https://codepen.io/aglgvsie/pen/QwEwNQz)                           |
| Eric         | [Codepen](https://codepen.io/wc-su/pen/GgqgqgX)                              |
| Sherry       | [Codepen](https://codepen.io/twvyqojd-the-typescripter/pen/MYeYKYE)          |
| RyanC        | [Codepen](https://codepen.io/RyanYD/pen/ByzyLVW)                             |
| 叮咚         | [Codepen](https://codepen.io/pinchieh-lin/pen/NPrPRmw)                       |
| Leonard      | [Codepen](https://codepen.io/hyyfjqra-the-sans/pen/pvbvPYM?editors=0011)     |
| Wafa         | [Codepen](https://codepen.io/dqricwgo-the-reactor/pen/yyJyPmM?editors=1111)  |
| kashiwatei   | [Codepen](https://codepen.io/kashiwatei/pen/yyJyjeX?editors=1111)            |
| 社子畢卡索   | [Codepen](https://codepen.io/pen?template=bNeNJOW)                           |
| ZoeKang      | [Codepen](https://codepen.io/byehywmx-the-animator/pen/dPXPxjx)              |
| Jin          | [Codepen](https://codepen.io/Jin-L/pen/gbMpOPj)                              |
| 舜仁         | [Codepen](https://codepen.io/shunjen/pen/bNedNLB)                            |
| 主委加碼啦幹 | [Codepen](https://codepen.io/popbob-the-bashful/pen/emzNNwY)                 |
| KOMATSU PEI  | [Codepen](https://codepen.io/Komatsu2021/pen/ByzyKVP?editors=1011)           |
| Miikaa       | [Codepen](https://codepen.io/Miikaa/pen/jErbNKK)                             |
| nonwa_jeff   | [codepen](https://codepen.io/nonwaaa/pen/qENOmaG)                            |
| Michelle     | [codepen](https://codepen.io/bastar_dize/pen/RNRWZKE?editors=1011)           |
| 小趴         | [Codpen](https://codepen.io/papa2415/pen/WbxQKVV)                            |
| 伊迪         | [Codpen](https://codepen.io/sorryFish/pen/VYjePKK)                           | 
| 蛋白         | [Codpen](https://codepen.io/sjlu-0/pen/YPWwOmB?editors=1010)                           | 
| 冠翔         | [Codpen](https://codepen.io/hsrfcdrx-the-bold/pen/KwMVeaq) |
|TWLeoC|[CodePan](https://codepen.io/TWLeoC/pen/PwzpXNw)|
| Wen        | [Codepen](https://codepen.io/hsiao-kevin/pen/EayvbOK?editors=1010)                           | 
| CharisLai       | [Codepen](https://codepen.io/charislai/pen/myEJyeY)                  | 
