生成UUID，生成32位随机字母加数字：（实用）

代码如下

var Util = {

randomUUID : function(){
    var chars = '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz'.split('')
    var uuid = new Array(36),
        rnd = 0,
        r
    for (var i = 0; i < 36; i++) {
        if (i === 8 || i === 13 || i == 18 || i == 23) {
            uuid[i] = '-'
        } else if (i === 14) {
            uuid[i] = '4'
        } else {
            if (rnd <= 0x02)
                rnd = 0x2000000 + (Math.random() * 0x1000000) | 0
            r = rnd & 0xf
            rnd = rnd >> 4
            uuid[i] = chars[(i == 19) ? (r & 0x3) | 0x8 : r]
        }
    }
    return uuid.join('').replace(/-/gm, '').toLowerCase()
}

}