问题
Is there a way to check to see if an iPhone is online from a web app. That is, in mobile Safari, can I check the online status of the device to see if I should try an AJAX call or not.
In Firefox/regular WebKit, this would be:
if(navigator.onLine)
{
onlineCode()
}
回答1:
img src="http://aonlinesite.com/a-really-little-image.png" onload="Intenet!" onerror="NoInternet!"
回答2:
A quick test on the iPhone shows that it is available from iPhone OS 2.2.
回答3:
That same code should work in the WebKit nightly build as of May 16th 2008. I guess that means you need to hope the 2.1 update included a new build of safari.
https://bugs.webkit.org/show_bug.cgi?id=19105
来源：https://stackoverflow.com/questions/66492/checking-online-status-from-an-iphone-web-app