UUID

######### PHP ##############

/**
* Generates an UUID
*
* @author Anis uddin Ahmad <admin@ajaxray.com>
* @param string an optional prefix
* @return string the formatted uuid
*/
function uuid($prefix='')
{
$chars = md5(uniqid(mt_rand(), true));
$uuid = substr($chars,0,8) . '-';
$uuid .= substr($chars,8,4) . '-';
$uuid .= substr($chars,12,4) . '-';
$uuid .= substr($chars,16,4) . '-';
$uuid .= substr($chars,20,12);
return $prefix . $uuid;
}

Example of using the function
-
//Using without prefix.

echo uuid();
//Returns like ‘1225c695-cfb8-4ebb-aaaa-80da344e8352′

//Using with prefix
echo uuid(‘urn:uuid:’);
//Returns like ‘urn:uuid:1225c695-cfb8-4ebb-aaaa-80da344e8352′

 

######### Javascript ##############

function guid() {
return 'xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx'.replace(/[xy]/g, function(c) {
var r = Math.random()*16|0, v = c == 'x' ? r : (r&0x3|0x8);
return v.toString(16);
});
}

..

function guid() {
function S4() {
return (((1+Math.random())*0x10000)|0).toString(16).substring(1);
}
return (S4()+S4()+"-"+S4()+"-"+S4()+"-"+S4()+"-"+S4()+S4()+S4());
}

..

function uuid(len, radix) {
var chars = '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz'.split('');
var uuid = [], i;
radix = radix || chars.length;

if (len) {
// Compact form
for (i = 0; i < len; i++) uuid[i] = chars[0 | Math.random()*radix];
} else {
// rfc4122, version 4 form
var r;

// rfc4122 requires these characters
uuid[8] = uuid[13] = uuid[18] = uuid[23] = '-';
uuid[14] = '4';

// Fill in random data. At i==19 set the high bits of clock sequence as
// per rfc4122, sec. 4.1.5
for (i = 0; i < 36; i++) {
if (!uuid[i]) {
r = 0 | Math.random()*16;
uuid[i] = chars[(i == 19) ? (r & 0x3) | 0x8 : r];
}
}
}

return uuid.join('');
}

 

// 8 character ID (base=2)
uuid(8, 2) // "01001010"
// 8 character ID (base=10)
uuid(8, 10) // "47473046"
// 8 character ID (base=16)
uuid(8, 16) // "098F4D35"

 

..

 

function uuid() {
var s = [];
var hexDigits = "0123456789abcdef";
for (var i = 0; i < 36; i++) {
s[i] = hexDigits.substr(Math.floor(Math.random() * 0x10), 1);
}
s[14] = "4"; // bits 12-15 of the time_hi_and_version field to 0010
s[19] = hexDigits.substr((s[19] & 0x3) | 0x8, 1); // bits 6-7 of the clock_seq_hi_and_reserved to 01
s[8] = s[13] = s[18] = s[23] = "-";

var uuid = s.join("");
return uuid;
}

 

 

..