请看这段代码:
<!DOCTYPE html>
<html>
<body>
<p id="P1"></p>
<script>
try {
alllllllert("Hello.........!");
}
catch(err) {
document.getElementById("P1").innerHTML = err.message;
}
</script>
</body>
</html>
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当此代码运行时,错误是警告,我进入catch块.
但是,为什么这不满足以下代码:
<!DOCTYPE html>
<html>
<body>
<p id="P1"></p>
<script>
try {
int n = 3;
document.getElementById("P1").innerHTML = n;
}
catch(err) {
document.getElementById("P1").innerHTML = err.message;
}
</script>
</body>
</html>
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编写int n = 3无法在JavaScript上编译,我知道我需要编写var n = 3.那么,为什么我没有收到消息的异常?