JavaScript异常
2017-03-30 本文已影响3人
Coder东
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>JavaScript错误-throw、try、和 catch</title>
</head>
<body>
<script>
var txt = "";
function message(){
try{
addlert("Welcome guest!");
}catch(err){
txt = "本页有一个错误。\n\n";
txt += "错误描述：" + err.message + "\n\n";
txt += "点击确定继续.\n\n";
alert(txt);
}
}
</script>
<input type="button" value="查看消息" onclick="message()" />
<p>请输入一个5到10之间的数字：</p>
<input id="demo" type="text" />
<button type="button" onclick="myFunction()" >测试输入：</button>
<p id="message"></p>
<script>
function myFunction(){
var message,x;
message = document.getElementById("message");
message.innerHTML = "";
x = document.getElementById("demo").value;
try{
if(x == "") throw "值为空";
if(isNaN(x)) throw "不是数字";
x = Number(x);
if(x<5) throw "太小";
if(x>10) throw "太大";
}catch(err){
message.innerHTML = "错误" + err;
}
}
</script>
</body>
</html>
