dizhi/index.html at master · guoyuejiang/dizhi · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
<!DOCTYPE html>
<html>
<head>
<script>
function ifUp(url,onUp,onDown) {
	// make random string
	var RANDOM_DIGITS = 7; // this is sufficient. Don't do more than ~12.
	var pow = Math.pow(10,RANDOM_DIGITS);
	var randStr = String(Math.floor(Math.random()*pow)+pow).substr(1);
	// create and load image
	var img = new Image();
	img.onload = onUp;
	img.onerror = onDown;
	img.src = url+"?"+randStr;
}

ifUp("https://www.yuhuage23.xyz/favicon.ico",
	function(){
		// do something
		window.location.href="https://www.yuhuage23.xyz";
	},
	function(){
		// do something else
		window.location.href="https://www.yuhuage23.xyz";
	}
);
</script>
</head>
<body>
</body>
</html>