一些上下文：
我有一张表格在页面加载时,我将表单序列化并保存在变量中.如果用户离开页面,我将该表单序列化并比较两者,以查看是否有任何更改.但是,如果表单被提交,则不应该触发该事件.
实施例1
我有这样工作的预期.我只是不明白两者之间的区别：
window.onbeforeunload = function(e) {
if(strOnloadForm != strUnloadForm)
return "You have unsaved changes.";
}
当您保存表单(绑定到.submit())时,此行停止触发
window.onbeforeunload = null;
示例2
window.addEventListener("beforeunload",function( event ) {
if(strOnloadForm != strUnloadForm)
event.returnValue = "You have unsaved changes.";
});
当您保存表单(绑定到.submit())时,此行停止触发
window.removeEventListener("beforeunload");
文件说明了什么
我已经阅读了onbeforeunload和beforeunload的文档.
在它之前说
You can and should handle this event through window.addEventListener() and the beforeunload event. More documentation is available there.
这让我觉得我应该使用后者.不过removeEventHandler的文档说：
addEventListener() and removeEventListener() are not present in older browsers. You can work around this by inserting the following code at the beginning of your scripts,allowing use of addEventListener() and removeEventListener() in implementations which do not natively support it.
有人可以请大家谈谈这些请求的差异,最好使用一下吗？
解决方法
window.addEventListener(“beforeunload”,function(){/ ** /});将添加一个新的处理程序.
addEventListener是首选.在旧版浏览器中(即IE6也许是IE7)可以使用attachEvent.
你通常会看到如下代码：
function addEvent(object,event_type,event_handler) {
if (object.addEventListener) {
object.addEventListener(event_type,event_handler,false);
} else {
object.attachEvent("on" + event_type,handler);
}
}
