加法 

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script type="application/javascript">
        window.onload = function () {
            var firstNubmer = document.getElementById('first');
            var secondNumber = document.getElementById('second');
            var btn = document.getElementById('btn');
            var result = document.getElementById('result');
            var remove = document.getElementById('remove');

            btn.onclick = function () {
                var firn = parseInt(firstNubmer.value);
                var secn = parseInt(secondNumber.value);
                var sum = firn + secn;
                result.value = sum;
            }

            remove.onclick = function () {
                firstNubmer.value = '';
                secondNumber.value = '';
                result.value = '';
            }

        }

    </script>
</head>
<body>
    <input type="text" id="first" > + <input type="text" id="second"> =
    <input type="text" id="result">
    <input type="button" id="btn" value="计算">
    <input type="button" id="remove" value="清除结果">

</body>
</html>

 

posted @ 2020-03-11 16:20  卢掌柜的  阅读(142)  评论(0)    收藏  举报