Utils一些常用的工具函数

 * @param {type} 类型
 *   type == 1 ---> "yyyy-mm-dd hh:MM:ss.fff"
 *   type == 2 ---> "yyyymmddhhMMss"
 *   type == '' ---> "yyyy-mm-dd hh:MM:ss"
 */
export const formatDate = (date, type) =>{
    var year = date.getFullYear();//年
    var month = date.getMonth() + 1 < 10 ? "0" + (date.getMonth() + 1) : date.getMonth() + 1;//月
    var day = date.getDate() < 10 ? "0" + date.getDate() : date.getDate();//日
    var hour = date.getHours() < 10 ? "0" + date.getHours() : date.getHours();//时
    var minutes = date.getMinutes() < 10 ? "0" + date.getMinutes() : date.getMinutes();//分
    var seconds = date.getSeconds() < 10 ? "0" + date.getSeconds() : date.getSeconds();//秒
    var milliseconds = date.getMilliseconds() < 10 ? "0" + date.getMilliseconds() : date.getMilliseconds() //毫秒
    if (type == 1) {
        return year + "-" + month + "-" + day + " " + hour + ":" + minutes + ":" + seconds + "." + milliseconds;
    } else if(type == 2){
        return year+""+month+""+day+""+hour+""+minutes+""+seconds;
    }else if(type == 3){
        return year + "-" + month + "-" + day;
    }else {
        return year + "-" + month + "-" + day + " " + hour + ":" + minutes + ":" + seconds;
    }
}

/**
 * 时间转换：20150101010101 --> '2015-01-01 01:01:01'
 */
export const parseToDate = (timeValue) => {
    var result = "";
    var year = timeValue.substr(0, 4);
    var month = timeValue.substr(4, 2);
    var date = timeValue.substr(6, 2);
    var hour = timeValue.substr(8, 2);
    var minute = timeValue.substr(10, 2);
    var second = timeValue.substr(12, 2);
    result = year + "-" + month + "-" + date + " " + hour + ":" + minute + ":" + second;
    return result;
}

/**
 * 返回两位的小数的字符串
 */
export const toFixedNum = (num) => {
    const tonum = Number(num).toFixed(2);
    return tonum;
}

**数组列表转树形结构**
const arrayToTree = (items, childName = 'children') => {
    const result = []; // 存放结果集
    const itemMap = {}; //
    for (const item of items) {
            const id = item.id;
            const pid = item.parentId;

            if (!itemMap[id]) {
                    itemMap[id] = {
                            [childName]: [],
                    };
            }
            itemMap[id] = {
                    ...item,
                    [childName]: itemMap[id][childName],
            };

            const treeItem = itemMap[id];

            if (pid === 0) {
                    result.push(treeItem);
            } else {
                    // if (!itemMap[pid]) {
                    // 	itemMap[pid] = {
                    // 		[childName]: [],
                    // 	};
                    // }
                    itemMap[pid][childName].push(treeItem);
            }
    }
    return result;
}

## 树形结构转扁平数组列表
const treeToList = (data, childName = 'children') => {
    // if (!Array.isArray(data)) {
    // 	return [];
    // }
    return data.reduce(
        (prev, cur) =>
            prev.concat([cur], treeToList(cur[childName] || [])),
        []
    );
};