以下代碼在提交時無法顯示錯誤消息。錯誤消息無法在簡單的JavaScript表單驗證中工作
問題是,單擊一次時錯誤消息顯示不正確,但如果您提供多次點擊,則可以正常工作。
幫助將不勝感激。
感謝
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta http-equiv="content-type" content="text/html; charset=utf-8" />
<title>JavaScript form validation - checking all letters</title>
<style type="text/css">
li {list-style-type: none;
font-size: 16pt;
}
.mail {
margin: auto;
padding-top: 10px;
padding-bottom: 10px;
width: 400px;
background : #D8F1F8;
border: 1px soild silver;
}
.mail h2 {
margin-left: 38px;
}
input {
font-size: 20pt;
}
input:focus, textarea:focus{
background-color: lightyellow;
}
input submit {
font-size: 12pt;
}
.rq {
color: #FF0000;
font-size: 10pt;
}
</style>
</head>
<body onload='document.form1.text1.focus()'>
<div class="mail">
<h2>Enter your Name and Submit</h2>
<form name="form1" action="#">
<ul>
<li>
Code:
</li>
<li id="myList">
<input type='text' name='text1'/>
<p id="error"></p>
</li>
<li class="rq">
*Enter alphabets only.
</li>
<li> </li>
<li>
<input type="submit" name="submit" value="Submit" onclick="allLetter(document.form1.text1)" />
</li>
<li> </li>
</ul>
</form>
</div>
<script type="text/javascript">
function allLetter(inputtxt) {
var letters = /^[A-Za-z]+$/;
if(inputtxt.value.match(letters)) {
document.getElementById("error").innerHTML="error here";
return false;
} else {
document.getElementById("error").innerHTML="success";
return true;
}
}
</script>
</body>
</html>
這裏同樣的問題https://stackoverflow.com/questions/4882691/javascript-error -val-match-is-not-a-function –
[Javascript錯誤:「val.match不是函數」]的可能重複(https://stackoverflow.com/questions/4882691/javascript-error-val-match - 這不是一個功能) – 2017-07-18 13:33:08