第一种

var str = "abcccwwwasdasfqwweqewqeqwnn"var arr = str.split("")var Arr = arr.sort()let num=1;let max="";let maxs=0;for(var i=0;i<Arr.length;i++){if(Arr[i]==Arr[i+1]){num++}else{if(num>maxs){maxs=nummax=Arr[i]}num=1}}console.log(max, maxs) 复制代码

第二种

var str = "abcccwwwasdasfqwweqewqeqwnn"var arr = str.split("")var Arr = arr.sort()var strs = Arr.join("");var max = "";var maxs = 0strs.replace(/(\w)\1+/g, function (strs, strs2) {if (strs.length > maxs) {maxs = strs.length;max = strs2}})console.log(max, maxs)复制代码

第三种

var str = "abcccwwwasdasfqwweqewqeqwnn"var o={}for(var i=0;i<str.length;i++){var name=str[i]if(o[name]){o[name]++}else{o[name]=1}}var max=0;var maxs=""for(var name in o){if(max<o[name]){max=name}}console.log(max,maxs)