<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<title>简单计算器</title>
</head>
<body>
<script>
var value1, value2;
value1 = window.prompt("请输入第一个运算数");
while(isNaN(value1)) {
alert("不是数值，请重新输入");
//alert('<br />');
value1 = window.prompt("请输入第一个运算数");
}
value2 = window.prompt("请输入第二个运算数");
while(isNaN(value2)) {
document.write("不是数值，请重新输入");
//document.write('<br />');
value2 = window.prompt("请输入第二个运算数");
}
function calculate() {
var result;
var operator = window.prompt("请输入运算符:+或-或*或/或%");
if(operator == "+") {
var result = parseInt(value1) + parseInt(value2);
alert(value1 + "+" + value2 + "=" + result);
} else if(operator == "-") {
var result = parseInt(value1) - parseInt(value2);
alert(value1 + "-" + value2 + "=" + result);
} else if(operator == "*") {
var result = parseInt(value1) * parseInt(value2);
alert(value1 + "*" + value2 + "=" + result);
} else if(operator == "/") {
if(value2 != 0) {
var result = parseInt(value1) / parseInt(value2);
alert(value1 + "/" + value2 + "=" + result);
} else {
alert("error！除数为0！");
}
} else if(operator == "%") {
var result = parseInt(value1) % parseInt(value2);
alert(value1 + "%" + value2 + "=" + result);
}
while(operator == "/" && value2 == 0) {
value2 = window.prompt("请输入第二个运算数");
//document.write('<br />');
var result = parseInt(value1) / parseInt(value2);
alert(value1 + "/" + value2 + "=" + result);
}
}
calculate();
</script>
</body>
</html>
如果除数为0，会提示，并重新输入第二个数。
效果图：
