如何让 Javascript 警报只显示一次，永远？
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How do I make a Javascript alert display only once, ever?
提问by Ben
I'm terrible at Javascript, but unfortunately, I need this one task completed. I need a Javascript alert to only display once--not once per browser session, but only once ever. I'm working on a project for a school competition; the alert will pertain to how Internet Explorer isn't compatible with my site and Chrome or Firefox is recommended. However, I don't want to pester the judges with pop-ups, so it only appearing up once would be best. I found the code that's displayed below online, but I can't make it work correctly. It may be something as simple as a parenthesis missing somewhere--again, I'm not good with Javascript, just HTML and CSS. :P If alternative code is encouraged to carry out my request, then by all means, suggest it! Thanks to all!
我在 Javascript 方面很糟糕，但不幸的是，我需要完成这一项任务。我需要一个JavaScript警告，只显示一次-每个浏览器会话不是一次，而是一次过。我正在为学校比赛做一个项目；警报将与 Internet Explorer 与我的网站不兼容的方式有关，建议使用 Chrome 或 Firefox。但是，我不想用弹出窗口来纠缠评委，所以最好只出现一次。我在网上找到了下面显示的代码，但我无法使其正常工作。它可能就像某个地方缺少括号一样简单——同样，我不擅长 Javascript，只擅长 HTML 和 CSS。:P 如果鼓励替代代码执行我的请求，那么无论如何，建议它！谢谢大家！
<script src="http://code.jquery.com/jquery-1.10.1.min.js"></script>
<!--[if IE]>
<script type="text/javascript">
$(document).one(function() { alert("You are using Internet Explorer to view this webpage. Your experience may be subpar while using Internet Explorer; we recommend using an alternative internet browser, such as Chrome or Firefox, to view our website."); } );
</script>
<![endif]-->
回答by dev7
oneis NOT what you need as a page refresh will override all the 'memory'.
one不是您需要的，因为页面刷新将覆盖所有“内存”。
You are most likely looking for localStorageor, if you are using internet explorer prior to version 8, use cookies:
您很可能正在寻找localStorage或者，如果您使用的是版本 8 之前的 Internet Explorer，请使用 cookie：
<script type="text/javascript">
var alerted = localStorage.getItem('alerted') || '';
if (alerted != 'yes') {
alert("You are using Internet Explorer to view this webpage. Your experience may be subpar while using Internet Explorer; we recommend using an alternative internet browser, such as Chrome or Firefox, to view our website.");
localStorage.setItem('alerted','yes');
}
</script>
EDIT:
编辑：
For IE versions prior to 8 you need to use cookies, since there is not suppor for localStorage. It's the exact same concept, just different methods. Take a look at this questionfor implementing cookies on your page.
对于 8 之前的 IE 版本，您需要使用 cookie，因为不支持localStorage. 这是完全相同的概念，只是方法不同。看看这个问题，以在您的页面上实施 cookie。
After you copied the code from the example, you should have 2 functions - createCookie()and getCookie().
从示例中复制代码后，您应该有 2 个函数 -createCookie()和getCookie().
var createCookie = function(name, value, days) {
....
//copy it from the other question
..
}
function getCookie(c_name) {
....
//copy it from the other question
..
}
<!--[if IE]>
<script type="text/javascript">
var alerted = getCookie('alerted') || '';
if (alerted != 'yes') {
alert("You are using Internet Explorer to view this webpage. Your experience may be subpar while using Internet Explorer; we recommend using an alternative internet browser, such as Chrome or Firefox, to view our website.");
createCookie('alerted','yes',365);//cookies expires after 365 days
}
</script>
<![endif]-->
Hope this helps!
希望这可以帮助！
