javascript - Auto Refresh a Page at Specific Time - Stack Overflow

admin管理员组

文章数量:1434388

I am trying to add some code to a chrome extension, that will refresh a specific page at a certain time of the day. I've found coding that involves adding meta tags to the header, or tags to the body but I cant edit the page's html so this is not possible. This is the code I have of now but it doesnt seem to be working --

    //60000 milliseconds is 1 minute
window.setInterval("checkForRefresh()", 60000);

function checkForRefresh() {
   var now = new Date();
   if (now.getHours() == 14 && now.getMinutes() == 24) {
      window.location.reload();
   }
}

It seems to have worked a couple of times, but now it just stopped working. Not sure what went wrong.

Any ideas on how to fix this?

I am trying to add some code to a chrome extension, that will refresh a specific page at a certain time of the day. I've found coding that involves adding meta tags to the header, or tags to the body but I cant edit the page's html so this is not possible. This is the code I have of now but it doesnt seem to be working --

    //60000 milliseconds is 1 minute
window.setInterval("checkForRefresh()", 60000);

function checkForRefresh() {
   var now = new Date();
   if (now.getHours() == 14 && now.getMinutes() == 24) {
      window.location.reload();
   }
}

It seems to have worked a couple of times, but now it just stopped working. Not sure what went wrong.

Any ideas on how to fix this?

• javascript
• jquery
• html
• google-chrome-extension
• refresh

Share Improve this question Follow edited Dec 10, 2013 at 19:57 730wavy asked Dec 10, 2013 at 18:45 730wavy730wavy 70411 gold badge2020 silver badges6565 bronze badges 6

• Are you using a content-script for that ? Also, keep in mind that the user might be in the middle of doing something on the page when the refresh happens and it can be veeery annoying ! – gkalpak Commented Dec 10, 2013 at 19:19
• Yeah Im using the content script. The user wont be doing nothing at the time because they will be awaiting a timer countdown to finish and for it to be a certain time of day where they will need to refresh the page exactly at that time of day. – 730wavy Commented Dec 10, 2013 at 19:27
• OK, then :) The solutions below should do the trick. BTW, if you want to develop an extension, you'll save a great deal of time by debugging easily resolved issues by yourself (instead of asking here). And when it es to debugging an extension the Developer Console is your best friend ! – gkalpak Commented Dec 10, 2013 at 19:30
• Ok thanks, Im familiar with the developer console so I think now that I've injected the jquery it should show up. – 730wavy Commented Dec 10, 2013 at 19:57
• You don't really need jQuery for this, but it won't hurt much either, I guess... – gkalpak Commented Dec 10, 2013 at 20:04

 |  Show 1 more ment

3 Answers 3

Sorted by: Reset to default 3

Use location.reload(true)

That'll reload the page and bypass the cache, however, if you don't want to bypass the cache, set then use location.reload(false)

Take a look at this.

window.refresh() is not a function. Try window.location.reload() instead.

For a more reliable and resource friendly solution, you could use the chrome.alarms API in a non-persistent background page (a.k.a. event page). E.g.:

In manifest.json:

{
    "manifest_version": 2,

    "name":    "Test Extension",
    "version": "0.0",
    "offline_enabled": false,

    "background": {
        "persistent": false,
        "scripts": ["background.js"]
    },

    "permissions": [
        "alarms",
        "tabs"
    ]
}

In background.js:

var refreshAlarmName = 'refreshAlarm';

/* Refresh at: 10 Dec 2013, 22:11:00 UTC */
var utcYear    = 2013;
var utcMonth   = 11;   // <-- watch out: this is zero-based
var utcDate    = 10;
var utcHours   = 22;
var utcMinutes = 11;

/* Convert a date (year, month, dayOfMonth, hours, mins)
 * to milliseconds past the epoch */
function at(year, month, dayOfMonth, hours, mins) {
    var date = new Date();

    date.setUTCFullYear(year);
    date.setUTCMonth(month);
    date.setUTCDate(dayOfMonth);
    date.setUTCHours(hours);
    date.setUTCMinutes(mins);
    date.setUTCSeconds(0);
    date.setUTCMilliseconds(0);

    return date.getTime();
}

chrome.alarms.create(refreshAlarmName, {
    when: at(utcYear, utcMonth, utcDate, utcHours, utcMinutes)
});

chrome.alarms.onAlarm.addListener(function(alarm) {
    if (alarm.name !== refreshAlarmName) {
        return;
    }

    chrome.tabs.query({ url: "*://www.eastbay./*" }, function(tabs) {
        tabs.forEach(function(tab) {
            chrome.tabs.reload(tab.id, { bypassCache: true });
        });
    });
});

---

Important note:

According to the docs:

For performance reasons, the alarm may have been delayed an arbitrary amount beyond this.

According to my experience, that arbitrary amount is hardly ever more than negligible, but if the exact timing is of the essence, you might want to consider a more sophisticated mechanism, where the background page fire's an alarm a couple of minutes before the target time, which injects a content script that sets a, say, 30secs interval to check for the target time and refresh.

本文标签： javascriptAuto Refresh a Page at Specific TimeStack Overflow