<script type="text/javascript">

        var arrObj = [];

        var str = 'good';

        var arr = str.split('');

        for (var i = 0; i < arr.length; i++) {

            var _j = -1;

            for (var j = 0; j < arrObj.length; j++) {

                if (arrObj[j].key == arr[i]) {//判断数组中是否已存在该字符串

                    _j = j;

                }

            }

            var num = arrObj[_j] != null ? (arrObj[_j].value + 1) : 1;

            if (_j != -1) { arrObj.splice(_j, 1); }

            arrObj.push({ key: arr[i], value: num });

        };

        for (var z = 0; z < arrObj.length; z++) {

            document.write(arrObj[z].key + arrObj[z].value);

        }

    </script>

        var arrObj = [];

        var str = 'goofo d';

        var arr = str.split('');

        for (var i = 0; i < arr.length; i++) {

            var _j = -1;

            for (var j = 0; j < arrObj.length; j++) {

                if (arrObj[j].key == arr[i]) {//判断数组中是否已存在该字母

                    _j = j;

                }

            }

            if (_j == -1) {

                if (arr[i] !== " ") {

                    arrObj.push({ key: arr[i], value: 1 });

                }

            }

            else if (_j != -1) {

                arrObj[_j].key = arr[i];

                arrObj[_j].value = arrObj[_j].value + 1;

            }

        };

        for (var z = 0; z < arrObj.length; z++) {

            console.log(arrObj[z].key + arrObj[z].value);

        }

      var obj = {}

        var arr = str.split("");

        arr.forEach(function (v, i) {

            obj[v] = obj[v] ? obj[v] + 1 : 1;

        });

        console.log(obj);