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JavaScript try ? catch
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JavaScript ?? try? catch? ??? ?????.
Syntax
try {
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} catch(err) {
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}
?:
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>php中文網(wǎng)(php.cn)</title>
<script type="text/javascript">
function message()
{
try
{
adlert("Hello World!");
}
catch(err)
{
alert("錯(cuò)啦！");
}
}
</script>
</head>
<body>
<input type = "button" value = "點(diǎn)擊" onclick = "message()">
</body>
</html>Throw ?
throw ? ?? ?? ??? ?? ??? ?????.
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try ? catch? ?? throw? ???? ???? ??? ???? ??? ?? ?? ???? ??? ? ????.
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throw ??
??? JavaScript ???, ??, ??? ?? ??? ? ????.
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>php.cn</title>
<script>
function myFunction(){
try{
var x=document.getElementById("demo").value;
if(x=="") throw "值為空";
if(isNaN(x)) throw "不是數(shù)字";
if(x>10) throw "太大";
if(x<5) throw "太小";
}
catch(err){
var y=document.getElementById("mess");
y.innerHTML="錯(cuò)誤：" + err + "。";
}
}
</script>
</head>
<body>
<p>請(qǐng)輸出一個(gè) 50 到 100 之間的數(shù)字:</p>
<input id="demo" type="text">
<button type="button" onclick="myFunction()">請(qǐng)輸入</button>
<p id="mess"></p>
</body>
</html>
