项目实训简易计算器

效果如下：

html


<!DOCTYPE html>
<html>
    <head>
        <meta http-equiv="Content-Type" content="text/html;charset=UTF-8">
        <script src="calculate.js"></script>
        <title>简易计算器</title>
        <style >@import url(calculate.css);</style>
    </head>
    <body>
        <div><h2>简易计算器</h2></div>
        <div>数1：<input type="number" name="" id="num1"></div>
        <div>数2：<input type="number" name="" id="num2"></div>
        <div>
            <input type="button" value="+" id="add" onclick　="add()">
            <input type="button" value="-" id="sub" onclick　="sub()">
            <input type="button" value="x" id="mul" onclick　="mul()">
            <input type="button" value="/" id="div" onclick　="div()">
        </div>
        <div>结果<input type="text" name="" id="res" value=""></div>
    </body>
</html>


function add(){
    var num1 = parseFloat(document.getElementById("num1").value);
    var num2 = parseFloat(document.getElementById("num2").value);
    document.getElementById("res").value = num1+num2;
}

function sub(){
    var num1 = parseFloat(document.getElementById("num1").value);
    var num2 = parseFloat(document.getElementById("num2").value);
    document.getElementById("res").value = num1-num2;
}

function mul(){
    var num1 = parseFloat(document.getElementById("num1").value);
    var num2 = parseFloat(document.getElementById("num2").value);
    document.getElementById("res").value = num1*num2;
}

function div(){
    var num1 = parseFloat(document.getElementById("num1").value);
    var num2 = parseFloat(document.getElementById("num2").value);
    document.getElementById("res").value = num1/num2;
}