判断一个字符串中出现次数最多的字符，统计这个次数

var str ='sdasdfgjdsasddddsgshs';var len = str.length;var tmp = {};function maxCharLen (str){    for(var i =0;i<len;i++){    if(!tmp[str.charAt(i)]){        tmp[str.charAt(i)] = 1;    }else{        tmp[str.charAt(i)]++;    }}var maxCount = 0;//字符出现最多的次数var tmpChar ='';//出现最多的字符    for(var i in tmp){        console.log(tmp);        if(tmp[i]>maxCount){            maxCount = tmp[i];            tmpChar = i;        }    }    return tmpChar+'出现的次数最多，为'+maxCount}