var str = "abcaaaaacdef";
//console.log(str.length);
var obj = {};
for(var i = 0; i < str.length; i++){
if( !obj[str.charAt(i)]){
obj[str.charAt(i)] = 1;
}else{
obj[str.charAt(i)]++;
}
}
//存出现次数最多的值和次数
var number = '';
var num = 0;
console.log("obj为：",obj); //Object {a: 6, b: 1, c: 2, d: 1, e: 1…}
//i代表每一项
for(var i in obj){
//console.log("i为：",i);
//obj[i] 为每一项的值
console.log("obj",obj[i]);
if(obj[i]>num){
num = obj[i];
number = i;
}
}
console.log("最终出现最多的字母是："+ number + ",次数为："+ num);//最终出现最多的字母是：a,次数为：6