JavaScript 必修篇 - 前端修練全攻略
本日為變數章節:變數與資料型別 ~ 變數:布林、undefined、null 章節的總複習!
請問以下變數的值、型別分別為何?
回覆格式:a = 值、型別
let a = 1 + "我好棒";
let b = 1 * "我好棒";
let c = 2 > 1;
let d = 1 < 2;
let e;
請利用賦值運算子計算冰箱布丁剩餘數量:
情境題 布丁剩多少?
冰箱裡原有 15 顆布丁
被妹妹拿走了 3 顆
被姊姊拿走了 5 顆
媽媽又冰了 10 顆
弟弟拿走了 2 顆
//請透過此變數進行運算
let puddingNum = 15;
console.log(`布丁還有${puddingNum}顆`)
小美去飲料店買了很多飲料,但她數學不好,請利用以下步驟幫小美算出購買總額:
- 1 杯紅茶 30 元
- 小美買了 2 杯
- 她將紅茶數量 * 紅茶價格,算出 60 元
- 1 杯綠茶 25 元
- 小美買了 4 杯
- 她將綠茶數量 * 綠茶價格,算出 ?? 元
- 1 杯奶茶 50元
- 小美買了 6 杯
- 她將奶茶數量 * 奶茶價格,算出 ?? 元
//帳單從零開始計算
let bill = 0 ;
const blackTeaPrice = 30;
let blackTeaNum = 2;
bill += blackTeaPrice*blackTeaNum;
//請接續步驟指引4,協助小美算出帳單金額
console.log(`小美總共花了${bill}元`)
請協助以下字串與數字轉型、過濾空白:
let number = "123";//將 number 轉型為數字
let string = 123;//將 string 轉型為字串
let myEmail =" 1235487@gmail.com";//請將 myEmail 的空白過濾掉
Fork 一份此範例,並將答案寫在 CodePen 複製 CodePen 連結貼至下方作業投稿區中回報就算完成了喔!
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