javascript - 跨浏览器onbeforeunload？

Question

是否window.onbeforeunload()在所有浏览器中触发？我需要一个至少由 IE6 和 FF3.6 支持的 onbeforeunload 功能。

对于 IE，onbeforeunload() 似乎只是 supported by IE9

Answer 1

我找到了一个使用 setTimeout 函数的 Firefox 解决方法，因为它的行为与其他网络浏览器不同。

window.onbeforeunload = function (e) {
    var message = "Are you sure ?";
    var firefox = /Firefox[\/\s](\d+)/.test(navigator.userAgent);

    if (firefox) {
        //Add custom dialog
        //Firefox does not accept window.showModalDialog(), window.alert(), window.confirm(), and window.prompt() furthermore
        var dialog = document.createElement("div");
        document.body.appendChild(dialog);
        dialog.id = "dialog";
        dialog.style.visibility = "hidden";
        dialog.innerHTML = message; 
        var left = document.body.clientWidth / 2 - dialog.clientWidth / 2;
        dialog.style.left = left + "px";
        dialog.style.visibility = "visible";  
        var shadow = document.createElement("div");
        document.body.appendChild(shadow);
        shadow.id = "shadow";       
        //tip with setTimeout
        setTimeout(function () {
            document.body.removeChild(document.getElementById("dialog"));
            document.body.removeChild(document.getElementById("shadow"));
        }, 0);
    }

    return message;
}

GitHub:https://github.com/Aelios/crossbrowser-onbeforeunload