生成某个范围内N个不重复随机数与生成固定长度数组

function getRndNum(num,min,max){
var n = [];
for(var i = min; i < max; i++){
n.push(i);
}
n.sort(function(){
return 0.5 - Math.random()
});
n.length = num;
return n;
}

// 生成某个长度数组
//let lenFun = length => Array.from({length}).map((v,k) => k);
 let lenFun = length => Array.from({length}, (v, k) => k);