--- tags: Vue 直播班 - 2022 春季班 --- # 🏅 Day 14 ###### tags: `Vue 直播班 - 2022 春季班` 參考文章: https://wcc723.github.io/javascript/2017/12/21/javascript-es6-arrow-function/ 教學 --- 箭頭函式的運用技巧如下: ```js= // 傳統函式 function saySomething(string) { return '接招' + string; } // 轉成箭頭函式 const saySomething = (string) => { return '接招 ' + string; } ``` ```js= // 當只有單行表達式時,可同時省略 return 及 {} // 省略後依然保有回傳的特質 const saySomething = (string) => '接招 ' + string; console.log(saySomething('菜鳥!')); // 不過要注意,如果有使用 {},就需要自行加上 return const saySomething = (string) => {'接招 ' + string}; console.log(saySomething('菜鳥!')); // 會回傳 undefined ``` ```js= // 只有一個參數可以不加括號 () const saySomething = string => '接招 ' + string; console.log(saySomething('菜鳥!')); // 沒有參數、參數有兩個以上都不能省略 () const saySomething = () => '接招 菜鳥!'; console.log(saySomething()); ``` 題目 (請貼上 CodePen) --- 請將以下程式碼簡化為箭頭函式 (不影響結果的情況下進行最大簡化) ```js= // 題目一 function sum(a, b) { let c = a + b; return c; } console.log(sum(5, 6)); // 題目二 function square(num) { return num * num; } console.log(square(5)) // 題目三 setTimeout(function() { console.log('延遲 1 秒'); }, 1000); // 題目四 let arr = [1, 2, 3]; let arrNew = arr.map(function(item, i) { return item * i; }); console.log(arrNew); // 題目五 let obj = { fn: function fn2(a) { return a * a; } } console.log(obj.fn(10)); ``` 回報流程 --- 請同學依照下圖教學觀看解答、回報答案: ![](https://i.imgur.com/QtL8zEW.png) 回報格式如下圖,請在「回報區」使用註解回報答案 (為了統計人數,請同學依序加上「報數」) ![](https://i.imgur.com/L7kyew8.png) <!-- 解答 // 題目一 const sum = (a, b) => { let c = a + b; return c; } console.log(sum(5, 6)); // 題目二 let square = num => num * num; console.log(square(5)); // 題目三 setTimeout(() => console.log('延遲 1 秒'), 1000); // 題目四 let arr = [1, 2, 3]; let arrNew = arr.map((item, i) => item * i); console.log(arrNew); // 題目五 let obj = { fn: a => a * a } console.log(obj.fn(10)); --> 回報區 --- | 報數 |組別/名字 | codepen / 其他回饋 | |:--------:| -------- | -------- | |1|CloThEs | https://codepen.io/bogwdnxx-the-sans/pen/mdBQogy| |2|Evan Chiang|https://codepen.io/piskesocute/pen/qBPQvew| |3| Larry | https://codepen.io/larrylinr5/pen/abLQMeP?editors=1111 | |4| Iris Huang | https://codepen.io/ythuang/pen/GRMwoJj | |5| kevin嘉軒 | https://codepen.io/kevin-chang-the-sasster/pen/NWaEmPj | |6| POPEYE | https://codepen.io/popeye_ux/pen/bGoQJdW | |7| 肉鬆 | https://codepen.io/klrkicog/pen/ExwOJNM?editors=0011 | |8|Wenfish|https://codepen.io/wenfisht/pen/dyVQLXy| |9|威爾|https://codepen.io/WILL_Wu/pen/gOGQyxg| |10|Joy Cheng| https://codepen.io/joycheng5432/pen/NWaEmYy?editors=0011| |11|Aaron Tu|https://codepen.io/aarontu/pen/vYeQMry| |12|Arista|https://codepen.io/arista-hsieh/pen/poWQBMG| |13|Liu| https://codepen.io/feng-chi-liu/pen/NWaEmVB?editors=1111 | |14|kevinhes|https://codepen.io/kevinhes/pen/xxXQNGV?editors=0012| |15|AllenW|https://codepen.io/AllenW/pen/gOGQyZx | |16|Jhen|https://codepen.io/cheng-jhen/pen/eYGQaJO | |17| Kelvin Hsu | https://codepen.io/kelvin001/pen/dyVQEXW?editors=1010 | |18|Howard|https://codepen.io/yawdnhbm/pen/mdBQYOX| |19|Sheep|https://codepen.io/SheepNDW/pen/KKXrYLb | |20|Yunei| https://codepen.io/Yunei/pen/NWaEVMm | |20|Yunei| https://codepen.io/emptywu/pen/JjreqvN | |22|Elaine Liu|https://codepen.io/elaine7598/pen/VwMVOYp?editors=0010| |23|Laura|https://codepen.io/minminn/pen/YzrRbZr| |24|Will|https://codepen.io/ncrdpepc-the-lessful/pen/mdBQYaG?editors=1012| |25|Gill|https://codepen.io/Gill-Chin/pen/OJxaYRE?editors=1011| |26|Bella Shya|https://codepen.io/BellaXie/pen/WNZYBqN?editors=0011 | |27|kk|https://codepen.io/potatokaka/pen/wvrQbVL?editors=0011| |28|有廖先生(Rain)|https://codepen.io/billpop741/pen/KKXrLJw| |29|Charlotte Lee|https://codepen.io/charlotte-lee/pen/vYeQqKv?editors=0010| |30| Meng | https://codepen.io/MGHN/pen/RwLqzBX?editors=0011 | |31|YC|https://codepen.io/YCLu/pen/eYGQZjB | |32|Yuan|https://codepen.io/yuanluo13542/pen/oNGQKLv?editors=0010 | |33|Beanhuang|https://codepen.io/Beanhuang/pen/GRMwVrj?editors=0011 | |34|Tim Lin|https://codepen.io/TimmyLin/pen/rNGQXqg| |35|Judy ☻|https://codepen.io/hsiaohan/pen/ZEXmgPZ?editors=0011 | |36|Pei Ying|https://codepen.io/hsiaohan/pen/ZEXmgPZ?editors=0011 | |37|andersonshen|https://codepen.io/luxyenni-the-bold/pen/zYEyOYx | |38| Benson |https://codepen.io/soul81624/pen/OJxrLOB | |39| 黃士桓 | https://codepen.io/shr-huan-huang/pen/wvrRwpR?editors=0011 | |40|Gui|https://codepen.io/guitimliu/pen/eYGbOGN |41|Henry| https://codepen.io/kaohenry9287/pen/rNGoBve | |42|Jerry|https://codepen.io/rteyfwwd-the-scripter/pen/abLPoWZ?editors=1112| |43|Calon|https://codepen.io/Calon0118/pen/jOGXNvN| |44|陳暐 |45|Scottie|https://codepen.io/wow767t/pen/zYEyYEp?editors=1111| |46|AKI|https://codepen.io/akichen27/pen/NWaEZxP| |47|Henry Wu|https://codepen.io/dkcmlaww-the-flexboxer/pen/WNZLbRZ?editors=1112 | |48|yu|https://codepen.io/yuu9916/pen/WNZLNNN?editors=1012 | |49|dOvOb|https://codepen.io/gezzgrwj-the-styleful/pen/LYzMppd?editors=0011 |50|Rick Tzeng|https://codepen.io/rick917jp6/pen/ZEXVboX |51| tingyu | https://codepen.io/dgltu/pen/GRMPoVv?editors=0011 | |52| shio | https://codepen.io/shioyen/pen/ZEXVQVP | |53|Himi|https://codepen.io/Himi/pen/poWqyNm| |54|Mylène|https://codepen.io/hamajibashi/pen/wvrRMVm| |55|咖咖|https://codepen.io/gon790219/pen/rNGoeqL | |56|海底藍|https://codepen.io/registermar3/pen/NWaerdq?editors=0011 | |57|Fleur|https://codepen.io/swwlee/pen/abLPvzL| |58|Otis|https://codepen.io/humming74/pen/poWqbXW?editors=0011 | |59|Terry21|https://codepen.io/feng0409/pen/poWqEJd?editors=0012 | |60|Yummyniya|https://codepen.io/yummyniya/pen/QWqzGgo| |61|柴貓|https://codepen.io/shibacat/pen/GRMPNJM| |62|nora-end|https://codepen.io/nora-shu/pen/YzrdZNP |63|Vicky|https://codepen.io/hyxfish27/pen/BawvZaE | |64|Bonnie|https://codepen.io/bonnieli1414/pen/LYzMLmg?editors=1010 | |65|John| https://codepen.io/jiangshuuu/pen/NWaXXWb | |66|Jasper|https://codepen.io/li-jasper/pen/WNZLJwj | |67|我是泇吟|https://codepen.io/kljuqbxs/pen/ZEXVomV| |68|DDDDK|https://codepen.io/dkklee/pen/oNGJdOb| |69|hua|https://codepen.io/hahahazzz123/pen/RwLEyeG?editors=1111| |70|Anna|https://codepen.io/kycrleao/pen/qBPLJpq?editors=0011| |71|Steven Chan|https://codepen.io/Steven1220/pen/yLzGRoW?editors=1011 | |72|William_O^2|https://codepen.io/CodingTrain_1/pen/bGoOOQY| |73|Jason Chen| https://codepen.io/jason60810/pen/MWELJRm | |74|阿武| https://codepen.io/samwnkyat/pen/GRMzXeq?editors=1111 | |75|小K|https://codepen.io/kelen1995/pen/QWqYYpx| |76| Sihle Huang | https://codepen.io/bugbug777/pen/eYGxQWz | |77|Jordan Tseng|https://codepen.io/jordan-ttc-design/pen/mdBobyr?editors=0011| |78|mei|https://codepen.io/Shila-Chen/pen/RwLdYgm| |79|肉桂卷|https://codepen.io/ginnlee/pen/eYGwJrd?editors=0011| |80|Abbie|https://codepen.io/Abbie0704/pen/OJxeQLe| |81|Jerry Yen|https://codepen.io/JerryYen/pen/zYEgmQj| |82|FuChang|https://codepen.io/fuchang830714/pen/zYEeOeB| |83|許敏鑫|https://codepen.io/MIN-HSIN/pen/BamBjXv?editors=1111| |84|阿劍| https://codepen.io/seonkuraito/pen/LYzqNoL | |85|Bruno Yu| https://codepen.io/bruno-yu/pen/YzEzzxo?editors=1111 |86|Hedy| https://codepen.io/hhhsuan41/pen/bGoQPLE?editors=0111 | |86| ShaoYu | https://codepen.io/shaoyukao/pen/xxPxBXz | |87|Riley|https://codepen.io/jjpxbprd/pen/zYPxxPX| |88|2/WA|https://codepen.io/ldddl/pen/podvgrK| |89|JD孟璁|https://codepen.io/oikdkmxq-the-looper/pen/MWOaZRQ?editors=1011| |90|andyii|https://codepen.io/gultrotpybyvue/pen/GROWEje |91| Van | https://codepen.io/fbacojji-the-selector/pen/RwjYPMo?editors=0011 | |92|大衛|https://codepen.io/exnsrpjc/pen/WNdxJJp?editors=1011 | |93|Carol Li|https://codepen.io/carolli834/pen/PoRBExW?editors=1011|