Javascript 在 PHP 页面上不起作用
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时间：2020-10-27 14:47:29 来源:igfitidea点击:
Javascript Not Working on PHP page
提问by Jake
I'm trying to code a checkbox that must be checked in order for the "Submit" button on a form to be enabled. I first tried using a linked file to no avail; now even inserting the script doesn't seem to work. Can anyone help? The entire code for the page is posted below. Thanks in advance!
我正在尝试编写一个复选框，必须选中该复选框才能启用表单上的“提交”按钮。我首先尝试使用链接文件无济于事；现在甚至插入脚本似乎也不起作用。任何人都可以帮忙吗？该页面的整个代码发布在下面。提前致谢！
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en">
<head>
<meta http-equiv="content-type" content="text/html; charset=utf-8" />
<link rel="stylesheet" type="text/css" href="stylesheet.css" />
<script type="text/javascript" src="includes/imagetransition.js"></script>
<script type="text/javascript" src="includes/checkenabledisable.js"></script>
<script type="text/javascript">
var checker = document.getElementById('acknowledgment');
var sendbtn = document.getElementById('submitmessage');
// when unchecked or checked, run the function
checker.onchange = function(){
if(this.checked){
sendbtn.disabled = false;
} else {
sendbtn.disabled = true;
}
}
</script>
<title>Contact Us</title>
</head>
<body>
<div class="page-wrapper">
<div id="header">
<img src="images/img1.jpg" name="slideshow" width="70%" height="200" alt="headerimage.gif"><br>
<a href="javascript:chgImg(-1)">Previous</a> |
<a href="javascript:auto()">Auto/Stop</a> |
<a href="javascript:chgImg(1)">Next</a></div>
<br><br>
<aside class="sidebar">
<div id="vmenu">
<ul>
<li class="sideli"><a href="main.html.php">Home</a></li>
<li class="sideli"><a href="areas.html.php">Areas</a></li>
<li class="sideli"><a href="profiles.html.php">Profiles</a></li>
<li class="sideli"><a href="contactus.html.php">Contact Us</a></li>
</ul>
</div>
</aside>
<section class="main">
We will review your submission and contact you, usually within 72 hours.</p>
<form action="actionemail.php" method="post">
<table class="emailtable">
<tr><td><label for="name" class="emaillabel">Name: </label></td><td><input type="text" name="fullname" size="50" value="Name" style="width: 290px;" /></td></tr>
<tr><td><label for="phone" class="emaillabel">Phone: </label></td><td><input type="text" name="phone" size="20" value="Phone" style="width: 290px;" /></td></tr>
<tr><td><label for="email" class="emaillabel">Email: </label></td><td><input type="text" name="email" size="50" value="Email" style="width: 290px;" /></td></tr>
<tr><td><label for="comment" class="emaillabel">Issue: </label></td><td><textarea rows="3" cols="26" name="comment" value="Tell Us More" style="width: 290px; height: 55px"></textarea></td></tr>
</table><br>
<input id="acknowledgment" type="checkbox" name="acknowledgment" value="1" /><label for="acknowledgment">I acknowledge that there may be a delay in responding to this request.</label><br>
<br><input id="submitmessage" type="submit" name ="submitmessage" value="Send Email" disabled />
</form>
</section>
</div>
</body>
</html>
采纳答案by Daniel Williams
Your function is not "listening" for an onchange event.
您的函数不是“监听” onchange 事件。
Use this instead. Notice I changed the checkbox to have an onclick event.
改用这个。请注意，我将复选框更改为具有 onclick 事件。
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en">
<head>
<meta http-equiv="content-type" content="text/html; charset=utf-8" />
<link rel="stylesheet" type="text/css" href="stylesheet.css" />
<script type="text/javascript" src="includes/imagetransition.js"></script>
<script type="text/javascript" src="includes/checkenabledisable.js"></script>
<script type="text/javascript">
function enableSubmitButton() {
if (document.getElementById("acknowledgment").checked == true)
document.getElementById("submitmessage").disabled = false;
}
</script>
<title>Contact Us</title>
</head>
<body>
<div class="page-wrapper">
<div id="header">
<img src="images/img1.jpg" name="slideshow" width="70%" height="200" alt="headerimage.gif"><br>
<a href="javascript:chgImg(-1)">Previous</a> |
<a href="javascript:auto()">Auto/Stop</a> |
<a href="javascript:chgImg(1)">Next</a></div>
<br><br>
<aside class="sidebar">
<div id="vmenu">
<ul>
<li class="sideli"><a href="main.html.php">Home</a></li>
<li class="sideli"><a href="areas.html.php">Areas</a></li>
<li class="sideli"><a href="profiles.html.php">Profiles</a></li>
<li class="sideli"><a href="contactus.html.php">Contact Us</a></li>
</ul>
</div>
</aside>
<section class="main">
We will review your submission and contact you, usually within 72 hours.</p>
<form action="actionemail.php" method="post">
<table class="emailtable">
<tr><td><label for="name" class="emaillabel">Name: </label></td><td><input type="text" name="fullname" size="50" value="Name" style="width: 290px;" /></td></tr>
<tr><td><label for="phone" class="emaillabel">Phone: </label></td><td><input type="text" name="phone" size="20" value="Phone" style="width: 290px;" /></td></tr>
<tr><td><label for="email" class="emaillabel">Email: </label></td><td><input type="text" name="email" size="50" value="Email" style="width: 290px;" /></td></tr>
<tr><td><label for="comment" class="emaillabel">Issue: </label></td><td><textarea rows="3" cols="26" name="comment" value="Tell Us More" style="width: 290px; height: 55px"></textarea></td></tr>
</table><br>
<input id="acknowledgment" type="checkbox" name="acknowledgment" value="1" onclick="enableSubmitButton()"><label for="acknowledgment">I acknowledge that there may be a delay in responding to this request.</label><br>
<br><input id="submitmessage" type="submit" name ="submitmessage" value="Send Email" disabled />
</form>
</section>
</div>
</body>
</html>
回答by Punitha
put some function name inside a script
将一些函数名放入脚本中
<script type="text/javascript">
function checker()
{
var checker = document.getElementById('acknowledgment');
var sendbtn = document.getElementById('submitmessage');
// when unchecked or checked, run the function
checker.onchange = function(){
if(this.checked){
sendbtn.disabled = false;
} else {
sendbtn.disabled = true;
}
}
}
</script>
and then you will call function in button onClick event
然后你将在按钮 onClick 事件中调用函数
<form action="actionemail.php" method="post">
<br><input id="submitmessage" type="submit" name ="submitmessage" value="Send Email" disabled onclick="checker();"/>
回答by Willem Van Onsem
You should place the javascript below the definition of the items. HTML is interpreted linearly. This means that the Javascript is executed in the beginning when no items is known as "acknowledgement"
您应该将 javascript 放在项目定义的下方。HTML 被线性解释。这意味着当没有项目被称为"acknowledgement"
