130.blob转file
/** *@param{blob}blob *@param{string}fileName */ exportconstblobToFile=(blob,fileName)=>{ blob.lastModifiedDate=newDate(); blob.name=fileName; returnblob; };
131.file转base64
/** *@param{*}file图片文件 */ exportconstfileToBase64=file=>{ letreader=newFileReader(); reader.readAsDataURL(file); reader.onload=function(e){ returne.target.result }; };
132.递归生成树形结构
exportfunctiongetTreeData(data,pid,pidName='parentId',idName='id',childrenName='children',key){ letarr=[]; for(leti=0;i<data.length;i ){ if(data[i][pidName]==pid){ data[i].key=data[i][idName]; data[i][childrenName]=getTreeData(data,data[i][idName],pidName,idName,childrenName); arr.push(data[i]); } } returnarr; }
133.遍历树节点
exportfunctionforeachTree(data,childrenName='children',callback){ for(leti=0;i<data.length;i ){ callback(data[i]); if(data[i][childrenName]&&data[i][childrenName].length>0){ foreachTree(data[i][childrenName],childrenName,callback); } } }
134.追溯父节点
exportfunctiontraceParentNode(pid,data,rootPid,pidName='parentId',idName='id',childrenName='children'){ letarr=[]; foreachTree(data,childrenName,(node)=>{ if(node[idName]==pid){ arr.push(node); if(node[pidName]!=rootPid){ arr=arr.concat(traceParentNode(node[pidName],data,rootPid,pidName,idName)); } } }); returnarr; }
135.寻找所有子节点
exportfunctiontraceChildNode(id,data,pidName='parentId',idName='id',childrenName='children'){ letarr=[]; foreachTree(data,childrenName,(node)=>{ if(node[pidName]==id){ arr.push(node); arr=arr.concat(traceChildNode(node[idName],data,pidName,idName,childrenName)); &bsp; }
});
return arr;
}
136.根据pid生成树形结构
/**
* @param { object } items 后台获取的数据
* @param { * } id 数据中的id
* @param { * } link 生成树形结构的依据
*/
export const createTree = (items, id = null, link = 'pid') =>{
items.filter(item => item[link] === id).map(item => ({ ...item, children: createTree(items, item.id) }));
};
137.查询数组中是否存在某个元素并返回元素第一次出现的下标
/**
* @param {*} item
* @param { array } data
*/
export function inArray(item, data) {
for (let i = 0; i < data.length; i++) {
if (item === data[i]) {
return i;
}
}
return -1;
}
138.Windows根据详细版本号判断当前系统名称
/**
* @param { string } osVersion
*/
export function OutOsName(osVersion) {
if(!osVersion){
return
}
let str = osVersion.substr(0, 3);
if (str === "5.0") {
return "Win 2000"
} else if (str === "5.1") {
return "Win XP"
} else if (str === "5.2") {
return "Win XP64"
} else if (str === "6.0") {
return "Win Vista"
} else if (str === "6.1") {
return "Win 7"
} else if (str === "6.2") {
return "Win 8"
} else if (str === "6.3") {
return "Win 8.1"
} else if (str === "10.") {
return "Win 10"
} else {
return "Win"
}
}
139.判断手机是Andoird还是IOS
/**
* 0: ios
* 1: android
* 2: 其它
*/
export function getOSType() {
let u = navigator.userAgent, app = navigator.appVersion;
let isAndroid = u.indexOf('Android') > -1 || u.indexOf('Linux') > -1;
let isIOS = !!u.match(/\(i[^;]+;( U;)? CPU.+Mac OS X/);
if (isIOS) {
return 0;
}
if (isAndroid) {
return 1;
}
return 2;
}
140.函数防抖
/**
* @param { function } func
* @param { number } wait 延迟执行毫秒数
* @param { boolean } immediate true 表立即执行,false 表非立即执行
*/
export function debounce(func,wait,immediate) {
let timeout;
return function () {
let context = this;
let args = arguments;
if (timeout) clearTimeout(timeout);
if (immediate) {
let callNow = !timeout;
timeout = setTimeout(() => {
timeout = null;
}, wait);
if (callNow) func.apply(context, args)
}
else {
timeout = setTimeout(() => {
func.apply(context, args)
}, wait);
}
}
}
145.函数节流
/**
* @param { function } func 函数
* @param { number } wait 延迟执行毫秒数
* @param { number } type 1 表时间戳版,2 表定时器版
*/
export function throttle(func, wait ,type) {
let previous, timeout;
if(type===1){
previous = 0;
}else if(type===2){
timeout = null;
}
return function() {
let context = this;
let args = arguments;
if(type===1){
let now = Date.now();
if (now - previous > wait) {
func.apply(context, args);
previous = now;
}
}else if(type===2){
if (!timeout) {
timeout = setTimeout(() => {
timeout = null;
func.apply(context, args)
}, wait)
}
}
}
}
146.判断数据类型
/**
* @param {*} target
*/
export function type(target) {
let ret = typeof(target);
let template = {
"[object Array]": "array",
"[object Object]":"object",
"[object Number]":"number - object",
"[object Boolean]":"boolean - object",
"[object String]":'string-object'
};
if(target === null) {
return 'null';
}else if(ret == "object"){
let str = Object.prototype.toString.call(target);
return template[str];
}else{
return ret;
}
}
147.生成指定范围随机数
/**
* @param { number } min
* @param { number } max
*/
export const RandomNum = (min, max) => Math.floor(Math.random() * (max - min + 1)) + min;
148.数组乱序
/**
* @param {array} arr
*/
export function arrScrambling(arr) {
let array = arr;
let index = array.length;
while (index) {
index -= 1;
let randomIndex = Math.floor(Math.random() * index);
let middleware = array[index];
array[index] = array[randomIndex];
array[randomIndex] = middleware
}
return array
}
150.数组交集
/**
* @param { array} arr1
* @param { array } arr2
*/
export const similarity = (arr1, arr2) => arr1.filter(v => arr2.includes(v));
151.数组中某元素出现的次数
/**
* @param { array } arr
* @param {*} value
*/
export function countOccurrences(arr, value) {
return arr.reduce((a, v) => v === value ? a + 1 : a + 0, 0);
}
152.加法函数(精度丢失问题)
/**
* @param { number } arg1
* @param { number } arg2
*/
export function add(arg1, arg2) {
let r1, r2, m;
try { r1 = arg1.toString().split(".")[1].length } catch (e) { r1 = 0 }
try { r2 = arg2.toString().split(".")[1].length } catch (e) { r2 = 0 }
m = Math.pow(10, Math.max(r1, r2));
return (arg1 * m + arg2 * m) / m
}
153.减法函数(精度丢失问题)
/**
* @param { number } arg1
* @param { number } arg2
*/
export function sub(arg1, arg2) {
let r1, r2, m, n;
try { r1 = arg1.toString().split(".")[1].length } catch (e) { r1 = 0 }
try { r2 = arg2.toString().split(".")[1].length } catch (e) { r2 = 0 }
m = Math.pow(10, Math.max(r1, r2));
n = (r1 >= r2) ? r1 : r2;
return Number(((arg1 * m - arg2 * m) / m).toFixed(n));
}
154.除法函数(精度丢失问题)
/**
* @param { number } num1
* @param { number } num2
*/
export function division(num1,num2){
let t1,t2,r1,r2;
try{
t1 = num1.toString().split('.')[1].length;
}catch(e){
t1 = 0;
}
try{
t2=num2.toString().split(".")[1].length;
}catch(e){
t2=0;
}
r1=Number(num1.toString().replace(".",""));
r2=Number(num2.toString().replace(".",""));
return (r1/r2)*Math.pow(10,t2-t1);
}
155.乘法函数(精度丢失问题)
/**
* @param { number } num1
* @param { number } num2
*/
export function mcl(num1,num2){
let m=0,s1=num1.toString(),s2=num2.toString();
try{m+=s1.split(".")[1].length}catch(e){}
try{m+=s2.split(".")[1].length}catch(e){}
return Number(s1.replace(".",""))*Number(s2.replace(".",""))/Math.pow(10,m);
}
156.递归优化(尾递归)
/**
* @param { function } f
*/
export function tco(f) {
let value;
let active = false;
let accumulated = [];
return function accumulator() {
accumulated.push(arguments);
if (!active) {
active = true;
while (accumulated.length) {
value = f.apply(this, accumulated.shift());
}
active = false;
return value;
}
};
}
157.生成随机整数
export function randomNumInteger(min, max) {
switch (arguments.length) {
case 1:
return parseInt(Math.random() * min + 1, 10);
case 2:
return parseInt(Math.random() * (max - min + 1) + min, 10);
default:
return 0
}
}
158.去除空格
/**
* @param { string } str 待处理字符串
* @param { number } type 去除空格类型 1-所有空格 2-前后空格 3-前空格 4-后空格 默认为1
*/
export function trim(str, type = 1) {
if (type && type !== 1 && type !== 2 && type !== 3 && type !== 4) return;
switch (type) {
case 1:
return str.replace(/\s/g, "");
case 2:
return str.replace(/(^\s)|(\s*$)/g, "");
case 3:
return str.replace(/(^\s)/g, "");
case 4:
return str.replace(/(\s$)/g, "");
default:
return str;
}
}
159.大小写转换
/**
* @param { string } str 待转换的字符串
* @param { number } type 1-全大写 2-全小写 3-首字母大写 其他-不转换
*/
export function turnCase(str, type) {
switch (type) {
case 1:
return str.toUpperCase();
case 2:
return str.toLowerCase();
case 3:
return str[0].toUpperCase() + str.substr(1).toLowerCase();
default:
return str;
}
}
160.随机16进制颜色 hexColor
/**
* 方法一
*/
export function hexColor() {
let str = '#';
let arr = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 'A', 'B', 'C', 'D', 'E', 'F'];
for (let i = 0; i < 6; i++) {
let index = Number.parseInt((Math.random() * 16).toString());
str += arr[index]
}
return str;
}
161.随机16进制颜色 randomHexColorCode
/**
* 方法二
*/
export const randomHexColorCode = () => {
let n = (Math.random() * 0xfffff * 1000000).toString(16);
return '#' + n.slice(0, 6);
};
162.转义html(防XSS攻击)
export const escapeHTML = str =>{
str.replace(
/[&<>'"]/g,
tag =>
({
'&': '&',
'<': '<',
'>': '>',
"'": ''',
'"': '"'
}[tag] || tag)
);
};
163.检测移动/PC设备
export const detectDeviceType = () => { return /Android|webOS|iPhone|iPad|iPod|BlackBerry|IEMobile|Opera Mini/i.test(navigator.userAgent) ? 'Mobile' : 'Desktop'; };
164.隐藏所有指定标签
/**
* 例: hide(document.querySelectorAll('img'))
*/
export const hideTag = (...el) => [...el].forEach(e => (e.style.display = 'none'));
165.返回指定元素的生效样式
/**
* @param { element} el 元素节点
* @param { string } ruleName 指定元素的名称
*/
export const getStyle = (el, ruleName) => getComputedStyle(el)[ruleName];
166.检查是否包含子元素
/**
* @param { element } parent
* @param { element } child
* 例:elementContains(document.querySelector('head'), document.querySelector('title')); // true
*/
export const elementContains = (parent, child) => parent !== child && parent.contains(child);
167.数字超过规定大小加上加号“+”,如数字超过99显示99+
/**
* @param { number } val 输入的数字
* @param { number } maxNum 数字规定界限
*/
export const outOfNum = (val, maxNum) =>{
val = val ? val-0 :0;
if (val > maxNum ) {
return `${maxNum}+`
}else{
return val;
}
};
168.如何隐藏所有指定的元素
const hide = (el) => Array.from(el).forEach(e => (e.style.display = 'none'));
// 事例:隐藏页面上所有`<img>`元素?
hide(document.querySelectorAll('img'))
169.如何检查元素是否具有指定的类?
页面DOM里的每个节点上都有一个classList对象,程序员可以使用里面的方法新增、删除、修改节点上的CSS类。使用classList,程序员还可以用它来判断某个节点是否被赋予了某个CSS类。
const hasClass = (el, className) => el.classList.contains(className)
// 事例
hasClass(document.querySelector('p.special'), 'special') // true
170.如何切换一个元素的类?
const toggleClass = (el, className) => el.classList.toggle(className)
// 事例 移除 p 具有类`special`的 special 类
toggleClass(document.querySelector('p.special'), 'special')
171.如何获取当前页面的滚动位置?
const getScrollPosition = (el = window) => ({
x: el.pageXOffset !== undefined ? el.pageXOffset : el.scrollLeft,
y: el.pageYOffset !== undefined ? el.pageYOffset : el.scrollTop
});
// 事例
getScrollPosition(); // {x: 0, y: 200}
172.如何平滑滚动到页面顶部
const scrollToTop = () => {
const c = document.documentElement.scrollTop || document.body.scrollTop;
if (c > 0) {
window.requestAnimationFrame(scrollToTop);
window.scrollTo(0, c - c / 8);
}
}
// 事例
scrollToTop()
window.requestAnimationFrame() 告诉浏览器——你希望执行一个动画,并且要求浏览器在下次重绘之前调用指定的回调函数更新动画。该方法需要传入一个回调函数作为参数,该回调函数会在浏览器下一次重绘之前执行。
requestAnimationFrame:优势:由系统决定回调函数的执行时机。60Hz的刷新频率,那么每次刷新的间隔中会执行一次回调函数,不会引起丢帧,不会卡顿。
window.requestAnimationFrame() 告诉浏览器——你希望执行一个动画,并且要求浏览器在下次重绘之前调用指定的回调函数更新动画。该方法需要传入一个回调函数作为参数,该回调函数会在浏览器下一次重绘之前执行。
requestAnimationFrame:优势:由系统决定回调函数的执行时机。60Hz的刷新频率,那么每次刷新的间隔中会执行一次回调函数,不会引起丢帧,不会卡顿。
173.如何检查父元素是否包含子元素?
const elementContains = (parent, child) => parent !== child && parent.contains(child);
// 事例
elementContains(document.querySelector('head'), document.querySelector('title'));
// true
elementContains(document.querySelector('body'), document.querySelector('body'));
// false
174.如何检查指定的元素在视口中是否可见?
const elementIsVisibleInViewport = (el, partiallyVisible = false) => {
const { top, left, bottom, right } = el.getBoundingClientRect();
const { innerHeight, innerWidth } = window;
return partiallyVisible
? ((top > 0 && top < innerHeight) || (bottom > 0 && bottom < innerHeight)) &&
((left > 0 && left < innerWidth) || (right > 0 && right < innerWidth))
: top >= 0 && left >= 0 && bottom <= innerHeight && right <= innerWidth;
};
// 事例
elementIsVisibleInViewport(el); // 需要左右可见
elementIsVisibleInViewport(el, true); // 需要全屏(上下左右)可以见
175.如何获取元素中的所有图像?
const getImages = (el, includeDuplicates = false) => {
const images = [...el.getElementsByTagName('img')].map(img => img.getAttribute('src'));
return includeDuplicates ? images : [...new Set(images)];
};
// 事例:includeDuplicates 为 true 表示需要排除重复元素
getImages(document, true); // ['image1.jpg', 'image2.png', 'image1.png', '...']
getImages(document, false); // ['image1.jpg', 'image2.png', '...']
176.如何确定设备是移动设备还是台式机/笔记本电脑?
const detectDeviceType = () =>
/Android|webOS|iPhone|iPad|iPod|BlackBerry|IEMobile|Opera Mini/i.test(navigator.userAgent)
? 'Mobile'
: 'Desktop';
// 事例
detectDeviceType(); // "Mobile" or "Desktop"
177.How to get the current URL?
const currentURL = () => window.location.href
// 事例
currentURL() // 'https://google.com'
178.如何创建一个包含当前URL参数的对象?
const getURLParameters = url =>
(url.match(/([^?=&]+)(=([^&]*))/g) || []).reduce(
(a, v) => ((a[v.slice(0, v.indexOf('='))] = v.slice(v.indexOf('=') + 1)), a),
{}
);
// 事例
getURLParameters('http://url.com/page?n=Adam&s=Smith'); // {n: 'Adam', s: 'Smith'}
getURLParameters('google.com'); // {}
179.如何将一组表单元素转化为对象?
const formToObject = form =>
Array.from(new FormData(form)).reduce(
(acc, [key, value]) => ({
...acc,
[key]: value
}),
{}
);
// 事例
formToObject(document.querySelector('#form'));
// { email: 'test@email.com', name: 'Test Name' }
180.如何从对象检索给定选择器指示的一组属性?
const get = (from, ...selectors) =>
[...selectors].map(s =>
s
.replace(/\[([^\[\]]*)\]/g, '.$1.')
.split('.')
.filter(t => t !== '')
.reduce((prev, cur) => prev && prev[cur], from)
);
const obj = { selector: { to: { val: 'val to select' } }, target: [1, 2, { a: 'test' }] };
// Example
get(obj, 'selector.to.val', 'target[0]', 'target[2].a');
// ['val to select', 1, 'test']
181.如何在等待指定时间后调用提供的函数?
const delay = (fn, wait, ...args) => setTimeout(fn, wait, ...args);
delay(
function(text) {
console.log(text);
},
1000,
'later'
);
// 1秒后打印 'later'
182.如何在给定元素上触发特定事件且能选择地传递自定义数据?
const triggerEvent = (el, eventType, detail) =>
el.dispatchEvent(new CustomEvent(eventType, { detail }));
// 事例
triggerEvent(document.getElementById('myId'), 'click');
triggerEvent(document.getElementById('myId'), 'click', { username: 'bob' });
自定义事件的函数有 Event、CustomEvent 和 dispatchEvent
// 向 window派发一个resize内置事件
window.dispatchEvent(new Event('resize'))
// 直接自定义事件,使用 Event 构造函数:
var event = new Event('build');
var elem = document.querySelector('#id')
// 监听事件
elem.addEventListener('build', function (e) { ... }, false);
// 触发事件.
elem.dispatchEvent(event);
CustomEvent 可以创建一个更高度自定义事件,还可以附带一些数据,具体用法如下:
var myEvent = new CustomEvent(eventname, options);
其中 options 可以是:
{
detail: {
...
},
bubbles: true, //是否冒泡
cancelable: false //是否取消默认事件
}
其中 detail 可以存放一些初始化的信息,可以在触发的时候调用。其他属性就是定义该事件是否具有冒泡等等功能。
内置的事件会由浏览器根据某些操作进行触发,自定义的事件就需要人工触发。
dispatchEvent 函数就是用来触发某个事件:
element.dispatchEvent(customEvent);
上面代码表示,在 element 上面触发 customEvent 这个事件。
// add an appropriate event listener
obj.addEventListener("cat", function(e) { process(e.detail) });
// create and dispatch the event
var event = new CustomEvent("cat", {"detail":{"hazcheeseburger":true}});
obj.dispatchEvent(event);
使用自定义事件需要注意兼容性问题,而使用 jQuery 就简单多了:
// 绑定自定义事件
$(element).on('myCustomEvent', function(){});
// 触发事件
$(element).trigger('myCustomEvent');
// 此外,你还可以在触发自定义事件时传递更多参数信息:
$( "p" ).on( "myCustomEvent", function( event, myName ) {
$( this ).text( myName + ", hi there!" );
});
$( "button" ).click(function () {
$( "p" ).trigger( "myCustomEvent", [ "John" ] );
});
183.如何从元素中移除事件监听器?
const off = (el, evt, fn, opts = false) => el.removeEventListener(evt, fn, opts);
const fn = () => console.log('!');
document.body.addEventListener('click', fn);
off(document.body, 'click', fn);
184.如何获得给定毫秒数的可读格式?
const formatDuration = ms => {
if (ms < 0) ms = -ms;
const time = {
day: Math.floor(ms / 86400000),
hour: Math.floor(ms / 3600000) % 24,
minute: Math.floor(ms / 60000) % 60,
second: Math.floor(ms / 1000) % 60,
millisecond: Math.floor(ms) % 1000
};
return Object.entries(time)
.filter(val => val[1] !== 0)
.map(([key, val]) => `${val} ${key}${val !== 1 ? 's' : ''}`)
.join(', ');
};
// 事例
formatDuration(1001); // '1 second, 1 millisecond'
formatDuration(34325055574);
// '397 days, 6 hours, 44 minutes, 15 seconds, 574 milliseconds'
185.如何获得两个日期之间的差异(以天为单位)?
const getDaysDiffBetweenDates = (dateInitial, dateFinal) =>
(dateFinal - dateInitial) / (1000 * 3600 * 24);
// 事例
getDaysDiffBetweenDates(new Date('2017-12-13'), new Date('2017-12-22')); // 9
186.如何向传递的URL发出GET请求?
const httpGet = (url, callback, err = console.error) => {
const request = new XMLHttpRequest();
request.open('GET', url, true);
request.onload = () => callback(request.responseText);
request.onerror = () => err(request);
request.send();
};
httpGet(
'https://jsonplaceholder.typicode.com/posts/1',
console.log
);
// {"userId": 1, "id": 1, "title": "sample title", "body": "my text"}
187.如何对传递的URL发出POST请求?
const httpPost = (url, data, callback, err = console.error) => {
const request = new XMLHttpRequest();
request.open('POST', url, true);
request.setRequestHeader('Content-type', 'application/json; charset=utf-8');
request.onload = () => callback(request.responseText);
request.onerror = () => err(request);
request.send(data);
};
const newPost = {
userId: 1,
id: 1337,
title: 'Foo',
body: 'bar bar bar'
};
const data = JSON.stringify(newPost);
httpPost(
'https://jsonplaceholder.typicode.com/posts',
data,
console.log
);
// {"userId": 1, "id": 1337, "title": "Foo", "body": "bar bar bar"}
188.如何为指定选择器创建具有指定范围,步长和持续时间的计数器?
const counter = (selector, start, end, step = 1, duration = 2000) => {
let current = start,
_step = (end - start) * step < 0 ? -step : step,
timer = setInterval(() => {
current += _step;
document.querySelector(selector).innerHTML = current;
if (current >= end) document.querySelector(selector).innerHTML = end;
if (current >= end) clearInterval(timer);
}, Math.abs(Math.floor(duration / (end - start))));
return timer;
};
// 事例
counter('#my-id', 1, 1000, 5, 2000);
// 让 `id=“my-id”`的元素创建一个2秒计时器
189.如何将字符串复制到剪贴板?
const el = document.createElement('textarea');
el.value = str;
el.setAttribute('readonly', '');
el.style.position = 'absolute';
el.style.left = '-9999px';
document.body.appendChild(el);
const selected =
document.getSelection().rangeCount > 0 ? document.getSelection().getRangeAt(0) : false;
el.select();
document.execCommand('copy');
document.body.removeChild(el);
if (selected) {
document.getSelection().removeAllRanges();
document.getSelection().addRange(selected);
}
};
// 事例
copyToClipboard('Lorem ipsum');
// 'Lorem ipsum' copied to clipboard
190.如何确定页面的浏览器选项卡是否聚焦?
const isBrowserTabFocused = () => !document.hidden;
// 事例
isBrowserTabFocused(); // true
191.如何创建目录(如果不存在)?
const fs = require('fs');
const createDirIfNotExists = dir => (!fs.existsSync(dir) ? fs.mkdirSync(dir) : undefined);
// 事例
createDirIfNotExists('test');
这里面的方法大都挺实用,可以解决很多开发过程问题,大家就好好利用起来吧。
192.日期型函数封装
function formatTime(date) {
if(!!date){
if(!(date instanceof Date))
date = new Date(date);
var month = date.getMonth() + 1
var day = date.getDate()
return `${month}月${day}日`;
}
}
function formatDay(date) {
if(!!date){
var year = date.getFullYear()
var month = date.getMonth() + 1
var day = date.getDate()
return [year, month, day].map(formatNumber).join('-');
}
}
function formatDay2(date) {
if(!!date){
var year = date.getFullYear()
var month = date.getMonth() + 1
var day = date.getDate()
return [year, month, day].map(formatNumber).join('/');
}
}
function formatWeek(date){
if(!!date){
var day = date.getDay();
switch (day) {
case 0:
return '周日'
break;
case 1:
return '周一'
break;
case 2:
return '周二'
break;
case 3:
return '周三'
break;
case 4:
return '周四'
break;
case 5:
return '周五'
break;
case 6:
return '周六'
break;
}
}
}
function formatHour(date){
if(!!date){
var hour = new Date(date).getHours();
var minute = new Date(date).getMinutes();
return [hour, minute].map(formatNumber).join(':');
}
}
function timestamp(date, divisor=1000){
if(date == undefined){
return;
}else if(typeof date == 'number'){
return Math.floor(date/divisor);
}else if(typeof date == 'string'){
var strs = date.split(/[^0-9]/);
return Math.floor(+new Date(strs[0] || 0,(strs[1] || 0)-1,strs[2] || 0,strs[3] || 0,strs[4] || 0,strs[5] || 0)/divisor);
}else if(Date.prototype.isPrototypeOf(date)){
return Math.floor(+date/divisor);
}
}
function detimestamp(date){
if(!!date){
return new Date(date*1000);
}
}
function formatNumber(n) {//给在0-9的日期加上0
n = n.toString()
return n[1] ? n : '0' + n
}
module.exports = {
formatTime: formatTime,
formatDay: formatDay,
formatDay2: formatDay2,
formatHour: formatHour,
formatWeek: formatWeek,
timestamp: timestamp,
detimestamp: detimestamp
}
193.时间戳转时间
/**
* 时间戳转化为年 月 日 时 分 秒
* number: 传入时间戳
* format:返回格式,支持自定义,但参数必须与formateArr里保持一致
*/
function formatTime(number,format) {
var formateArr = ['Y','M','D','h','m','s'];
var returnArr = [];
var date = new Date(number * 1000);
returnArr.push(date.getFullYear());
returnArr.push(formatNumber(date.getMonth() + 1));
returnArr.push(formatNumber(date.getDate()));
returnArr.push(formatNumber(date.getHours()));
returnArr.push(formatNumber(date.getMinutes()));
returnArr.push(formatNumber(date.getSeconds()));
for (var i in returnArr)
{
format = format.replace(formateArr[i], returnArr[i]);
}
return format;
}
//数据转化
function formatNumber(n) {
n = n.toString()
return n[1] ? n : '0' + n
}
调用示例:
var sjc = 1488481383;//时间戳
console.log(time.formatTime(sjc,'Y/M/D h:m:s'));//转换为日期:2017/03/03 03:03:03
console.log(time.formatTime(sjc, 'h:m'));//转换为日期:03:03
194.js中获取上下文路径
js中获取上下文路径
//js获取项目根路径,如: http://localhost:8083/uimcardprj
function getRootPath(){
//获取当前网址,如: http://localhost:8083/uimcardprj/share/meun.jsp
var curWwwPath=window.document.location.href;
//获取主机地址之后的目录,如: uimcardprj/share/meun.jsp
var pathName=window.document.location.pathname;
var pos=curWwwPath.indexOf(pathName);
//获取主机地址,如: http://localhost:8083
var localhostPaht=curWwwPath.substring(0,pos);
//获取带"/"的项目名,如:/uimcardprj
var projectName=pathName.substring(0,pathName.substr(1).indexOf('/')+1);
return(localhostPaht+projectName);
}
195.JS大小转化B KB MB GB的转化方法
function conver(limit){
var size = "";
if( limit < 0.1 * 1024 ){ //如果小于0.1KB转化成B
size = limit.toFixed(2) + "B";
}else if(limit < 0.1 * 1024 * 1024 ){//如果小于0.1MB转化成KB
size = (limit / 1024).toFixed(2) + "KB";
}else if(limit < 0.1 * 1024 * 1024 * 1024){ //如果小于0.1GB转化成MB
size = (limit / (1024 * 1024)).toFixed(2) + "MB";
}else{ //其他转化成GB
size = (limit / (1024 * 1024 * 1024)).toFixed(2) + "GB";
}
var sizestr = size + "";
var len = sizestr.indexOf("\.");
var dec = sizestr.substr(len + 1, 2);
if(dec == "00"){//当小数点后为00时 去掉小数部分
return sizestr.substring(0,len) + sizestr.substr(len + 3,2);
}
return sizestr;
}
196.js全屏和退出全屏
function fullScreen() {
var el = document.documentElement;
var rfs = el.requestFullScreen || el.webkitRequestFullScreen || el.mozRequestFullScreen || el.msRequestFullScreen;
//typeof rfs != "undefined" && rfs
if (rfs) {
rfs.call(el);
} else if (typeof window.ActiveXObject !== "undefined") {
//for IE,这里其实就是模拟了按下键盘的F11,使浏览器全屏
var wscript = new ActiveXObject("WScript.Shell");
if (wscript != null) {
wscript.SendKeys("{F11}");
}
}
}
//退出全屏
function exitScreen() {
var el = document;
var cfs = el.cancelFullScreen || el.webkitCancelFullScreen || el.mozCancelFullScreen || el.exitFullScreen;
//typeof cfs != "undefined" && cfs
if (cfs) {
cfs.call(el);
} else if (typeof window.ActiveXObject !== "undefined") {
//for IE,这里和fullScreen相同,模拟按下F11键退出全屏
var wscript = new ActiveXObject("WScript.Shell");
if (wscript != null) {
wscript.SendKeys("{F11}");
}
}
}
197.格式化时间,转化为几分钟前,几秒钟前
/**
* 格式化时间,转化为几分钟前,几秒钟前
* @param timestamp 时间戳,单位是毫秒
*/
function timeFormat(timestamp) {
var mistiming = Math.round((Date.now() - timestamp) / 1000);
var arrr = ['年', '个月', '星期', '天', '小时', '分钟', '秒'];
var arrn = [31536000, 2592000, 604800, 86400, 3600, 60, 1];
for (var i = 0; i < arrn.length; i++) {
var inm = Math.floor(mistiming / arrn[i]);
if (inm != 0) {
&