JavaScript_10_错误

Try...catch...

throw

<!DOCTYPE html>
<html>
<head>
    <title></title>
    <meta charset="utf-8" />
</head>
<body>

    <h1>异常处理程序</h1>
    <p>请输入5到10之间的数字</p>
    <input id="txt" type="text" />
    <button type="button" onclick="myfunction()">测试输入值</button>
    <p id="mess"></p>
    <script>
        function myfunction()
        {
            try
            {
                var x = document.getElementById("txt").value; //如果这句话也有错误，同样能捕捉到异常
                if (x == "") throw "值为空";
                if (isNaN(x)) throw "不是数字";
                if (x > 10) throw "太大";
                if (x < 5) throw "太小";
            }
            catch (err)
            {
                var y = document.getElementById("mess");
                y.innerHTML = "错误：" + err + "。 ";
            }
        }
    </script>

</body>
</html>

 

posted @ 2017-03-23 10:25  HepburnXiao  阅读(122)  评论(0)    收藏  举报