JS 三个对话框
<!DOCTYPE html>
<html lang="en" xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta charset="utf-8" />
<title></title>
<script>
//alert(123);
//点确定返回true，点取消返回false
//var result = confirm('确实要删除吗？');
//alert(result);
//点确定返回输入的值，点取消返回null
var result = prompt('请输入年龄', '10');
alert(result);
</script>
</head>
<body>
</body>
</html>
<html lang="en" xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta charset="utf-8" />
<title></title>
<script>
//alert(123);
//点确定返回true，点取消返回false
//var result = confirm('确实要删除吗？');
//alert(result);
//点确定返回输入的值，点取消返回null
var result = prompt('请输入年龄', '10');
alert(result);
</script>
</head>
<body>
</body>
</html>
