function randomSort(a, b) {
return Math.random() > 0.5 ? -1 : 1;
}

var arr = [1,2,3,4,5,6,7,8,9];
arr.sort(randomSort);

function randomSort(arr, newArr) {
// 如果原数组arr的length值等于1时，原数组只有一个值，其键值为0
// 同时将这个值push到新数组newArr中
if(arr.length == 1) {
newArr.push(arr[0]);
return newArr; // 相当于递归退出
}
// 在原数组length基础上取出一个随机数
var random = Math.ceil(Math.random() * arr.length) - 1;
// 将原数组中的随机一个值push到新数组newArr中
newArr.push(arr[random]);
// 对应删除原数组arr的对应数组项
arr.splice(random,1);
return randomSort(arr, newArr);
}

for (var i = 0; i < 10; i++) {
var arr=[1,2,3,4,5,6,7,8,9];
var newArr=[];
randomSort(arr,newArr);
console.log(newArr);
}

Array.prototype.shuffle = function(n) {
var len = this.length ,
num = n ? Math.min(n,len) : len,
arr = this.slice(0);
arr.sort(function(a,b){
return Math.random()-0.5;
});
return arr.slice(0,num-1);
}

lib = {}
lib.range = function(min,max) {
return min + Math.floor(Math.random()*(max-min+1));
}

Array.prototype.shuffle = function(n) {
var len = this.length,
num = n ? Math.min(n,len) : len,
arr = this.slice(0),
temp,
index;
for (var i=0;i<len;i++){
index = lib.range(i,len-1);
temp = arr[i];
arr[i] = arr[index];
arr[index]=temp;
}
return arr.slice(0,num);
}

lib = {}
lib.range = function(min,max) {
return min+Math.floor(Math.random()*(max-min+1));
}
Array.prototype.shuffle = function(n) {
var len = this.length, 
num = n ? Math.min(n,len) : len,
arr = this.slice(0),
result=[],
index;
for (var i=0;i<num;i++){
index = lib.range(0,len-1-i);
// 或者 result.concat(arr.splice(index,1))
result.push(arr.splice(index,1)[0]);
}
return result
}

function random(min, max) {
if (max == null) {
max = min;
min = 0;
}
return min + Math.floor(Math.random() * (max - min + 1));
};
function shuffle(arr) {
var length = arr.length,
shuffled = Array(length);
for (var index = 0, rand; index < length; index++) {
rand = random(0, index);
if (rand !== index) shuffled[index] = shuffled[rand];
shuffled[rand] = arr[index];
}
return shuffled;
}

var arr = [1,2,3,4,5,6,7,8,9];
for (var i = 0; i < 10; i++){
console.log(shuffle(arr));
}

function shuffle(arr) {
var i, 
j,
temp;
for (i = arr.length - 1; i > 0; i--) {
j = Math.floor(Math.random() * (i + 1));
temp = arr[i];
arr[i] = arr[j];
arr[j] = temp;
}
return arr;
};