在这里的stackoverflow，如果你开始做改变，然后你试图导航离开页面，一个javascript确认按钮显示，并询问:“你确定你想导航离开这个页面吗?”
以前有人实现过这个吗?我如何跟踪已提交的更改?
我相信我自己可以做到这一点，我正在努力从你们这些专家那里学习好的做法。
我尝试了以下方法，但仍然不起作用:
<html>
<body>
<p>Close the page to trigger the onunload event.</p>
<script type="text/javascript">
var changes = false;
window.onbeforeunload = function() {
if (changes)
{
var message = "Are you sure you want to navigate away from this page?\n\nYou have started writing or editing a post.\n\nPress OK to continue or Cancel to stay on the current page.";
if (confirm(message)) return true;
else return false;
}
}
</script>
<input type='text' onchange='changes=true;'> </input>
</body>
</html>
有人能举个例子吗?
从webapi ->WindowEventHandler->onbeforeunload，它建议使用window.addEventListener()和beforeunload事件，而不是onbeforeunload。
语法的例子
window.addEventListener("beforeunload", function(event) { ... });
window.onbeforeunload = function(event) { ... };
注意:HTML规范规定作者应该使用Event. preventdefault()方法而不是使用Event。returnValue来提示用户。
所以，就你的情况而言，代码应该是这样的:
//javascript
window..addEventListener("beforeunload", function(event) {
//your code
// If you prevent default behaviour in Mozilla Firefox prompt will always be shown
e.preventDefault();
// Chrome requires returnValue to be set
e.returnValue = '';
})
这是我的HTML
<!DOCTYPE HMTL>
<meta charset="UTF-8">
<html>
<head>
<title>Home</title>
<script type="text/javascript" src="script.js"></script>
</head>
<body onload="myFunction()">
<h1 id="belong">
Welcome To My Home
</h1>
<p>
<a id="replaceME" onclick="myFunction2(event)" href="https://www.ccis.edu">I am a student at Columbia College of Missouri.</a>
</p>
</body>
这就是我用javaScript做的类似事情
var myGlobalNameHolder ="";
function myFunction(){
var myString = prompt("Enter a name", "Name Goes Here");
myGlobalNameHolder = myString;
if (myString != null) {
document.getElementById("replaceME").innerHTML =
"Hello " + myString + ". Welcome to my site";
document.getElementById("belong").innerHTML =
"A place you belong";
}
}
// create a function to pass our event too
function myFunction2(event) {
// variable to make our event short and sweet
var x=window.onbeforeunload;
// logic to make the confirm and alert boxes
if (confirm("Are you sure you want to leave my page?") == true) {
x = alert("Thank you " + myGlobalNameHolder + " for visiting!");
}
}
