一些js随机操作

// 获取数组随机值
function GetRandomNum(arr) {
  var Max = arr.length - 1;
  var Range = Max;
  var Rand = Math.random();
  var index = Math.round(Rand * Range);
  return arr[index];
}

// 获取随机 mac 地址
function GetRandomMac() {
  var arr = '0123456789abcdef';
  var macstr = '';
  for(var i = 0; i < 12; i++) {
    var Rand = Math.random();
    var index = Math.round(Rand * 15);
    if(0 == (i % 2) && i > 0) {
	macstr += ':';
    }
    macstr += arr[index];
  }
  return macstr;
}

// 获取随机 Uuid
function GetRandomUuid() {
  var uuidstr = '';
  for(var i = 0; i < 15; i++) {
	var Rand = Math.random();
	var index = Math.round(Rand * 9);
	uuidstr += index;
  }
  return uuidstr;
}

// 获取随机 anid
function GetRandomAnid() {
  var arr = '0123456789abcdef';
  var anidstr = '';
  for(var i = 0; i < 16; i++) {
	var Rand = Math.random();
	var index = Math.round(Rand * 15);
	anidstr += arr[index];
  }
  return anidstr;
}