我的方法是:

使用onpopstate监听url中的变化，并将sessionStorage变量设置为1 监听页面加载并将sessionStorage变量设置为0 在beforeunload上，检查变量是否为0。如果是这样，这意味着用户正在关闭而不是改变url。

这仍然是一条迂回的路，但对我来说是有意义的

Sorry, I was not able to add a comment to one of existing answers, but in case you wanted to implement a kind of warning dialog, I just wanted to mention that any event handler function has an argument - event. In your case you can call event.preventDefault() to disallow leaving the page automatically, then issue your own dialog. I consider this a way better option than using standard ugly and insecure alert(). I personally implemented my own set of dialog boxes based on kendoWindow object (Telerik's Kendo UI, which is almost fully open-sourced, except of kendoGrid and kendoEditor). You can also use dialog boxes from jQuery UI. Please note though, that such things are asynchronous, and you will need to bind a handler to onclick event of every button, but this is all quite easy to implement.

然而，我同意缺少真正的关闭事件是很糟糕的:例如，如果你想在真正关闭的情况下才在后端重置会话状态，这是一个问题。

正如@jAndy提到的，没有合适的javascript代码来检测一个窗口正在关闭。 我从@Syno的提议开始。

我曾经遇到过类似的情况，只要你遵循这些步骤，你就能发现它。 我在Chrome 67+和Firefox 61+上进行了测试。

var wrapper = function () { //ignore this

var closing_window = false;
$(window).on('focus', function () {
    closing_window = false; 
   //if the user interacts with the window, then the window is not being 
   //closed
});

$(window).on('blur', function () {

    closing_window = true;
    if (!document.hidden) { //when the window is being minimized
        closing_window = false;
    }
    $(window).on('resize', function (e) { //when the window is being maximized
        closing_window = false;
    });
    $(window).off('resize'); //avoid multiple listening
});

$('html').on('mouseleave', function () {
    closing_window = true; 
    //if the user is leaving html, we have more reasons to believe that he's 
    //leaving or thinking about closing the window
});

$('html').on('mouseenter', function () {
    closing_window = false; 
    //if the user's mouse its on the page, it means you don't need to logout 
    //them, didn't it?
});

$(document).on('keydown', function (e) {

    if (e.keyCode == 91 || e.keyCode == 18) {
        closing_window = false; //shortcuts for ALT+TAB and Window key
    }

    if (e.keyCode == 116 || (e.ctrlKey && e.keyCode == 82)) {
        closing_window = false; //shortcuts for F5 and CTRL+F5 and CTRL+R
    }
});

// Prevent logout when clicking in a hiperlink
$(document).on("click", "a", function () {
    closing_window = false;
});

// Prevent logout when clicking in a button (if these buttons rediret to some page)
$(document).on("click", "button", function () {
    closing_window = false;

});
// Prevent logout when submiting
$(document).on("submit", "form", function () {
    closing_window = false;
});
// Prevent logout when submiting
$(document).on("click", "input[type=submit]", function () {
    closing_window = false;
});

var toDoWhenClosing = function() {

    //write a code here likes a user logout, example: 
    //$.ajax({
    //    url: '/MyController/MyLogOutAction',
    //    async: false,
    //    data: {

    //    },
    //    error: function () {
    //    },
    //    success: function (data) {
    //    },
    //});
};


window.onbeforeunload = function () {
    if (closing_window) {
        toDoWhenClosing();
    }
};

};

window.onbeforeunload = function ()
{       

    if (isProcess > 0) 
    {
        return true;       
    }   

    else
    { 
        //do something      
    }
}; 

此功能在浏览器运行过程中关闭窗口或刷新页面时显示确认对话框。该函数适用于所有浏览器。你必须在ajax进程中设置isProcess var。

试试这个, 我相信这对你有用。

<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.js"></script>
<script type='text/javascript'>
    $(function() {

        try{
            opera.setOverrideHistoryNavigationMode('compatible');
            history.navigationMode = 'compatible';
        }catch(e){}

        function ReturnMessage()
        {
            return "wait";
        }

        function UnBindWindow()
        {
            $(window).unbind('beforeunload', ReturnMessage);
        }

        $(window).bind('beforeunload',ReturnMessage );
    });
</script>

如果我没说错，你想知道什么时候一个标签/窗口是有效关闭的。好吧，在JavaScript中检测这个的唯一方法是使用onunload或onbeforeunload事件。

不幸的是(或幸运的是?)，当您通过链接或浏览器的后退按钮离开网站时，这些事件也会被触发。这是我能给出的最好答案，我不认为你能在JavaScript中原生检测纯close。如果我说错了，请指正。