bd-short-message-platform/app/middleware/utils/getArr.js

// 截取数组元素，组成新数组并返回
module.exports = (arr, start, end) => {
    let newArr = [];
    arr.forEach((element, index) => {
        if (index >= start && index <= end) {
            newArr.push(element);
        }
    });
    return newArr;
};