前端
2018-12-05 本文已影响0人
周肸
1.计算器
<!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;
//不做此判断会弹出“NaN”
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>计算器</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="" id="input02"/>
<input type="button" name="" value="计算" id="btn">
</body>
</html>
2. switch语句练习
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
<script type="text/javascript">
var today = prompt("请输入数字:");
switch(today){
case "1":
alert("星期一");
break
case "2":
alert("星期二");
break
case "3":
alert("星期三");
break
case "4":
alert("星期四");
break
case "5":
alert("星期五");
break
case "6":
alert("星期六");
break
case "7":
alert("星期日");
break
default:
alert("输入不对");
}
</script>
</head>
<body>
</body>
</html>
