//返回一个指定范围内的随机数 function createRandomNum(Min,Max){ let Range = Max - Min; let Rand = Math.random(); return(Min + Math.round(Rand * Range)); } createRandomNum(2,11); //3 //返回一个指定长度的随机字符串 let chars = ['0','1','2','3','4','5','6','7','8','9','A','B','C'