JavaScript开发中常用的方法集介绍

function dateFormat(fmt, date) {

let ret;

let opt = {

“Y+”: date.getFullYear().toString(), // 年

“M+”: (date.getMonth() + 1).toString(), // 月

“D+”: date.getDate().toString(), // 日

“h+”: date.getHours().toString(), // 时

“m+”: date.getMinutes().toString(), // 分

“s+”: date.getSeconds().toString(), // 秒

“ms+”: date.getMilliseconds().toString() // 毫秒

};

for (let k in opt) {

ret = new RegExp(“(” + k + “)”).exec(fmt);

if (ret) {

fmt = fmt.replace(ret[1], ret[1].length == 1 ? opt[k] : opt[k].padStart(ret[1].length, “0”));

}

}

return fmt;

}

let date = new Date();

let fDate = dateFormat(“YYYY-MM-DD hh:mm:ss.ms”, new Date(date));

function timeDiffer(beginTime, endTime) {

let ret = {};

let date = new Date();

let sTime = Date.parse(dateFormat(“YYYY/MM/DD”, date) + ” ” + beginTime);

if (beginTime >= endTime) {

date.setDate(date.getDate() + 1);

}

let eTime = Date.parse(dateFormat(“YYYY/MM/DD”, date) + ” ” + endTime);

let differ = eTime – sTime;

let hour = Math.floor(differ / 1000 / 60 / 60);

let minute = Math.floor(differ / 1000 / 60 – hour * 60);

let second = Math.floor(differ / 1000 – hour * 60 * 60);

ret = {

differHour: hour,

differMinute: minute,

differSecond: second

};

return ret;

}

let { differHour, differMinute, differSecond } = timeDiffer(beginTime, endTime);

function deepCopy(obj) {

if (typeof obj !== “object”) {

return obj;

}

let result = Array.isArray(obj) ? [] : {};

for (let i in obj) {

if (obj.hasOwnProperty(i)) {

if (typeof obj[i] === “object” && obj[i] !== null) {

result[i] = deepCopy(obj[i]);

} else {

result[i] = obj[i];

}

}

}

return result;

}

let result = [];

if (Array.isArray(arr)) {

result = new Set(arr);

}

// 数组去重

function unique(arr) {

if (!Array.isArray(arr)) {

return;

}

let result = [];

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

if (result.indexOf(arr[i]) === -1) {

result.push(arr[i]);

}

}

return result;

}

list.sort((a, b) => {

return a.id.localeCompare(b.id);

});