loops; simple to do list - LilyLiya

while loop VS if loop:

while loop, we don't know when the loop will stop, if loop, we know how many times the loop will run.

FOR......OF......

let subarrays = ['hello', 'hi', 'how are you'];

for (let sub of subarrays) {
    console.log(sub);
}

Nested For...Of

const SECRET = "HiBye";

let guess = prompt("enter the secret code……");
while(guess !== SECRET){
     guess = prompt("enter the secret code……");
}
console.log("Congrats you got the secret !!!")

To-do-list project

<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Todo List</title>
</head>

<body>
    <h1>Todo List</h1>

    <ul>
        <li>"new" -Add a Todo</li>
        <li>"list" - List All Todos</li>
        <li>"delete" - Remove Specific Todo</li>
        <li>"quit" - Quit App</li>
    </ul>
    <script src="todos.js"></script>
</body>

</html>

let input = prompt("what would you like to do?");

const todos = [];

while (input !== "quit" && input !== "q") {
    if (input === "list") {
        console.log("**********")
        for (let i = 0; i < todos.length; i++) {
            console.log(`${i}: ${todos[i]}`);
        }
        console.log("**********")
    } else if (input === "new") {
        const newTodo = prompt("ok, what is the new todo?");
        todos.push(newTodo);
        console.log(`${newTodo} added into the list`)
    } else if (input === "delete") {
        const index = parseInt(prompt("ok, enter an index to delete"));
        if (!Number.isNaN(index)) {
            const deleted = todos.splice(index, 1);
            console.log(`ok, deleted ${deleted[0]}`);
        } else {
            console.log("Unknow index")
        }
    }
    input = prompt("what would you like to do?")
}
console.log("ok, quit the app")

posted on 2021-01-11 03:52 LilyLiya 阅读(82) 评论(0) 收藏举报

刷新页面返回顶部