计算机

计算机
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>计算机</title>
<script type="text/javascript">
    window.onload = function () {
        var oInput01 = document.getElementById("input01");
        var oInput02 = document.getElementById("input02");
        var oSelect = document.getElementById("select");
        var oBtn = document.getElementById("btn");

        oBtn.onclick = function () {
            var val01 = oInput01.value;
            var val02 = oInput02.value;

            if(val01=="" || val02==""){
                alert('输入框不能为空！');
                return;
            }
            if(isNaN(val01) || isNaN(val02)){
                alert('请输入数字！');
                return;
            }
            switch (oSelect.value) {
                case "0":
                    alert((parseFloat(val01)*100 + parseFloat(val02)*100)/100);
                    break;
                case "1":
                    alert((parseFloat(val01)*100 - parseFloat(val02)*100)/100);
                    break;
                case "2":
                    alert((parseFloat(val01)*100) * (parseFloat(val02)*100)/10000);
                    break;
                case "3":
                    alert((parseFloat(val01)*100) / (parseFloat(val02)*100));
                    break;
            }
        }
    }
</script>
</head>
<body>
<h1>计算机</h1>
<input type="text" name="" id="input01" />
<select id="select">
    <option value="0">+</option>
    <option value="1">-</option>
    <option value="2">*</option>
    <option value="3">/</option>
</select>
<input type="text" name="" value="" id="input02">
<input type="button" name="" value="计算" id="btn">
</body>
推荐阅读更多精彩内容
