(ES6的“...“配合ES5‘’forEach‘’)前端面試之判斷一個字串中出現次數最多的字元，統計這個次數

// 判斷一個字串中出現次數最多的字元，統計這個次數
let str = 'aasdadddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddsdasjjhsghkafsagjkgfasgj;ksagj;lagsjlgjlsagjl;sajlk;gsasdadaaa';
// 得到字元陣列
let strArr = [...str];
let obj = {};
strArr.forEach((items, index) => {
  if (obj[items]) obj[items]++;
  else obj[items] = 1;
});
// 獲取物件的key陣列
let keyArr = Object.keys(obj)
let max = null
keyArr.forEach((items, index) => {
  if (index === 0) max = items
  else if (obj[max] < obj[items]) max = items
})
console.log(obj);
console.log(max + '出現的次數是' + obj[max]);
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