四则运算switch 运用

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>四则运算</title>
</head>
<body>
<button onclick="cc()"/>点击进行四则运算</button>
<script type="text/javascript">
function cc(){
    var number1=prompt("请输入第一个数字","");
        number1=parseFloat(number1);
    var number2=prompt("请输入第二个数字","");
        number2=parseFloat(number2);
    var operator=prompt("请输入运算符","");
    var res=0;
    switch(operator){
        case "+":
            res=number1+number2
            break;
        case "-":
            res=number1-number2 
            break;
        case "*":
            res=number1*number2
            break;
        case"/":
            res=number1/number2
            break;
    }
    alert(number1+operator+number2+"="+res)
}

</script>   
</body>
</html>
posted @ 2018-05-05 09:29  dongdongyang  阅读(472)  评论(0)    收藏  举报