与window global关键字一起使用:-

 window.localStorage.removeItem('keyName');

for (let i = 0; i < localStorage.length; i++) {
    if (localStorage.key(i).indexOf('the-name-to-delete') > -1) {
        arr.push(localStorage.key(i));
    }
}

for (let i = 0; i < arr.length; i++) {
    localStorage.removeItem(arr[i]);
}

在这个问题被提出6年后，我发现这个问题仍然没有足够的答案;这应该实现以下所有:

关闭浏览器(或域的所有选项卡)后清除本地存储 如果至少有一个选项卡保持活动状态，则跨选项卡保留本地存储 重新加载单个选项卡时保留本地存储

在每个页面加载开始时执行这段javascript代码，以实现上述目标:

((nm,tm) => {
    const
            l = localStorage,
            s = sessionStorage,
            tabid = s.getItem(tm) || (newid => s.setItem(tm, newid) || newid)((Math.random() * 1e8).toFixed()),
            update = set => {
                let cur = JSON.parse(l.getItem(nm) || '{}');
                if (set && typeof cur[tabid] == 'undefined' && !Object.values(cur).reduce((a, b) => a + b, 0)) {
                    l.clear();
                    cur = {};
                }
                cur[tabid] = set;
                l.setItem(nm, JSON.stringify(cur));
            };
    update(1);
    window.onbeforeunload = () => update(0);
})('tabs','tabid');

编辑:这里的基本思想如下:

When starting from scratch, the session storage is assigned a random id in a key called tabid The local storage is then set with a key called tabs containing a object those key tabid is set to 1. When the tab is unloaded, the local storage's tabs is updated to an object containing tabid set to 0. If the tab is reloaded, it's first unloaded, and resumed. Since the session storage's key tabid exists, and so does the local storage tabs key with a sub-key of tabid the local storage is not cleared. When the browser is unloaded, all session storage will be cleared. When resuming the session storage tabid won't exists anymore and a new tabid will be generated. Since the local storage does not have a sub-key for this tabid, nor any other tabid (all session were closed), it's cleared. Upon a new created tab, a new tabid is generated in session storage, but since at least one tabs[tabid] exists, the local storage is not cleared

sessionStorage使用

sessionStorage对象与localStorage对象相同，只是它只存储一个会话的数据。当用户关闭浏览器窗口时，数据将被删除。

下面的例子统计用户在当前会话中点击按钮的次数:

例子

if (sessionStorage.clickcount) {
    sessionStorage.clickcount = Number(sessionStorage.clickcount) + 1;
} else {
    sessionStorage.clickcount = 1;
}
document.getElementById("result").innerHTML = "You have clicked the button " +
sessionStorage.clickcount + " time(s) in this session.";

下面是一个简单的测试，看看你在使用本地存储时是否有浏览器支持:

if(typeof(Storage)!=="undefined") {
  console.log("localStorage and sessionStorage support!");
  console.log("About to save:");
  console.log(localStorage);
  localStorage["somekey"] = 'hello';
  console.log("Key saved:");
  console.log(localStorage);
  localStorage.removeItem("somekey");  //<--- key deleted here
  console.log("key deleted:");
  console.log(localStorage);
  console.log("DONE ===");
} else {
  console.log("Sorry! No web storage support..");
}

它为我工作如预期(我使用谷歌Chrome)。 改编自:http://www.w3schools.com/html/html5_webstorage.asp。

8.5年过去了，最初的问题一直没有得到答案。

当浏览器关闭时，没有一个标签。

这个基本代码片段将为您提供两全其美的服务。仅在浏览器会话期间存在的存储(如sessionStorage)，但也可以在选项卡之间共享(localStorage)。

它完全通过localStorage来实现这一点。

function cleanup(){
    // place whatever cleanup logic you want here, for example:
    // window.localStorage.removeItem('my-item')
}

function tabOpened(){
    const tabs = JSON.parse(window.localStorage.getItem('tabs'))
    if (tabs === null) {
        window.localStorage.setItem('tabs', 1)
    } else {
        window.localStorage.setItem('tabs', ++tabs)
    }
}

function tabClosed(){
    const tabs = JSON.parse(window.localStorage.getItem('tabs'))
    if (tabs === 1) {
        // last tab closed, perform cleanup.
        window.localStorage.removeItem('tabs')
        cleanup()
    } else {
        window.localStorage.setItem('tabs', --tabs)
    }
}

window.onload = function () {
    tabOpened();
}

window.onbeforeunload = function () {
    tabClosed();
}