劉子鳴JavaScript亂數random捨去小數floor進位ceil四捨五入round

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343介紹物件object

RANDOM亂數,FLOOR捨去尾數,CEIL進位,ROUND

輸入整數

Math.random()亂數Method方法

Math.floor()捨去小數Method方法

Math.ceil()進位Method

Math.round()四捨Method

以轉寫模式上傳程式碼

輸入整數<input type="number" id="n" value=7 min=1 max=1000/>

<button onclick="abc()">劉子鳴執行</button>

<h3>Math.random()亂數Method方法</h3>

<p id="demo"></p>

<h3>Math.floor()捨去小數Method方法</h3>

<p id="demo1"></p>

<h3>Math.ceil()進位Method</h3>

<p id="demo2"></p>

<h3>Math.round()四捨Method</h3>

<p id="demo3"></p>

<script>

function abc(){

let n = document.getElementById("n").value;

let x = Math.random()*n;

document.getElementById("demo").innerHTML = x;

document.getElementById("demo1").innerHTML = Math.floor(x);

document.getElementById("demo2").innerHTML = Math.ceil(x);

document.getElementById("demo3").innerHTML = Math.round(x);}

</script>

新增的重要指令

輸入數字N<input value=7 type="number" id="n" min="1" max="9"/>

<button onclick="abc()">劉任昌執行</button>

script 程式部分

function abc(){

let n = document.getElementById("n").value;

let x = Math.random()*n;

...}