js常用代码收集

1. PC - js

  • 返回指定范围的随机数(m-n之间)的公式
Math.random()*(n-m)+m
// event.preventDefault()会阻挡预设要发生的事件.
// event.stopPropagation()会阻挡发生冒泡事件.
// 而return false则是前面两者的事情他都会做: // 他会做event.preventDefault(); // 他会做event.stopPropagation(); // 停止callback function的执行并且立即return回来
  • 复制文本到剪切板
function copyToClipboard(data) {
    const _tempInput = document.createElement('input') _tempInput.value = data.value document.body.appendChild(_tempInput) _tempInput.select() document.execCommand('Copy') document.body.removeChild(_tempInput) }
  • 前端生成文件并下载
function createAndDownloadFile(fileName, content) {
    const aTag = document.createElement('a'); const blob = new Blob([content]); aTag.download = `${fileName}.json`; aTag.href = URL.createObjectURL(blob); aTag.click(); URL.revokeObjectURL(blob); }
  • 高亮文本
function highlight(text, words, tag='span') { let i, len = words.length, re; for (i = 0; i < len; i++) { re = new RegExp(words[i], 'g'); if (re.test(text)) { text = text.replace(re, '<'+ tag +' class="highlight">$&</'+ tag +'>'); } } return text; } 
  • 限制文本字数
function excerpt(str, nwords) {
    let words = str.split(' '); words.splice(nwords, words.length-1); return words.join(' ') + (words.length !== str.split(' ').length ? '…' : ''); }
  • 简单创建动态菜单下拉列表
function createMenu(items, tags=['ul', 'li']) { const parent = tags[0]; const child = tags[1]; let item, value = ''; for (let i = 0, l = items.length; i < l; i++) { item = items[i]; if (/:/.test(item)) { item = items[i].split(':')[0]; value = items[i].split(':')[1]; } items[i] = '<'+ child +' '+ (value && 'value="'+value+'"') +'>'+ item +'</'+ child +'>'; } return '<'+ parent +'>'+ items.join('') +'</'+ parent +'>'; }
  • 防止被Iframe嵌套
if(top != self){
    location.href = ”about:blank”; }
  • 两种图片lazy加载的方式 第一个By JS中级交流群 成都-猎巫 第二个By 上海-zenki
// @description 准备为图片预加载使用的插件
// 使用的图片容器css类名为lazy-load-wrap
// 图片真实地址为data-lazy-src // 当lazy-load-wrap容器进入视口,则开始替换容器内所有需要延迟加载的图片路径,并更改容器的加载状态 //第一种方法 $.fn.compassLazyLoad=function(){ var _HEIGHT=window.innerHeight, _lazyLoadWrap=$('.lazy-load-wrap'); var methods={ setOffsetTop:function(){ $.each(_lazyLoadWrap,function(i,n){ $(n).attr({ 'top':n.offsetTop-_HEIGHT, 'status':'wait' }); }) }, isShow:function(){ var _scrollTop=$(window).scrollTop; //利用image容器判断是否进入视口,而非image本身 $.each(_lazyLoadWrap,function(){ var _that=$(this); if (_that.attr('status')==='done') { return; }; if (_that.attr('top')<=_scrollTop) { _that.find('img[data-lazy-src]').each(function(i,n){ n.src=$(n).data('lazy-src'); }); _that.attr('status','done'); }; }) }, scroll:function(){ $(window).on('scroll',function(){ methods.isShow(); }); }, init:function(){ methods.setOffsetTop(); methods.isShow(); methods.scroll(); } }; methods.init(); } //第二种方法 var exist=(function($){ var timer=null, temp=[].slice.call($('.container')); ret={}; for(var i=0,len=temp.length-1;i<=len;i++){ ret[i]=temp[i]; } var isExist=function(winTop,winEnd){ for(var i in ret){ console.log(ret); var item=ret[i], eleTop=item.offsetTop, eleEnd=eleTop+item.offsetHeight; if((eleTop>winTop&&eleTop<=winEnd)||(eleEnd>winTop&&eleEnd<=winEnd)){ $(item).css('background','none'); new Tab($(item).attr('id'),data).init; delete ret[i]; } } } return { timer:timer; isExist:isExist; }; })($); //第三种方法 Zepto(function ($) { var swiper = new Swiper('.swiper-container', { pagination: '.swiper-pagination', paginationClickable: true, autoplay: 3000, loop: true, autoplayDisableOnInteraction: false }); (function lazyLoad() { var imgs = $(".lazyLoad"); var src = ''; $.each(imgs, function (index, item) { src = $(item).attr('data-src'); $(item).attr('src', src); }); })(); }); $(function () { var lazyLoadTimerId = null; /// 智能加载事件 $(window).bind("scroll", function () { clearTimeout(lazyLoadTimerId); lazyLoadTimerId = setTimeout(function () { // 延迟加载所有图片 var isHttp = (location.protocol === "http:"); $("#ym_images img").each(function () { var self = $(this); if (self.filter(":above-the-fold").length > 0) { var originUrl = self.attr("data-original"); self.attr("src", originUrl); } }); }, 500); }); }); 
  • 某年某月的1号为星期几
var weekday = ["星期日", "星期一", "星期二", "星期三", "星期四", "星期五", "星期六"]; weekday[new Date(2015, 9, 1).getDay()]; //2015年10月1号

2. Mobile - js

var u = navigator.userAgent, app = navigator.appVersion; var isAndroid = u.indexOf('Android') > -1 || u.indexOf('Linux') > -1; //android终端或者uc浏览器 var isiOS = !!u.match(/\(i[^;]+;( U;)? CPU.+Mac OS X/); //ios终端 alert('是否是Android:'+isAndroid); alert('是否是iOS:'+isiOS);

3. 微信 weixin

  • UserAgent 判断微信客户端
// Mozilla/5.0 (iPhone; CPU iPhone OS 8_3 like Mac OS X) AppleWebKit/600.1.4 (KHTML, like Gecko) Mobile/12F70 MicroMessenger/6.1.5 NetType/WIFI
function isWechat() {  
    var ua = navigator.userAgent.toLowerCase(); return /micromessenger/i.test(ua) || /windows phone/i.test(ua); }
  • 获取单个dom元素
function $(selector, el) {
  if (!el) { el = document; } return el.querySelector(selector); }
  • 获取多个dom元素
function $$(selector, el) {
  if (!el) { el = document; } return el.querySelectorAll(selector); // Note: the returned object is a NodeList. // If you'd like to convert it to a Array for convenience, use this instead: // return Array.prototype.slice.call(el.querySelectorAll(selector)); }
  • 将nodeList集合转换为数组
function convertToArray(nodeList) {
  var array = null try { // IE8-NodeList是COM对象 array = Array.prototype.slice.call(nodeList, 0) } catch (err) { array = [] for (var i = 0, len = nodeList.length; i < len; i++) { array.push(nodeList[i]) } } return array }
  • ajax函数
function ajax(setting) {
  //设置参数的初始值
  var opts = { method: (setting.method || "GET").toUpperCase(), //请求方式 url: setting.url || "", // 请求地址 async: setting.async || true, // 是否异步 dataType: setting.dataType || "json", // 解析方式 data: setting.data || "", // 参数 success: setting.success || function () { }, // 请求成功回调 error: setting.error || function () { } // 请求失败回调 }; // 参数格式化 function params_format(obj) { var str = ""; for (var i in obj) { str += i + "=" + obj[i] + "&"; } return str .split("") .slice(0, -1) .join(""); } // 创建ajax对象 var xhr = new XMLHttpRequest(); // 连接服务器open(方法GET/POST,请求地址, 异步传输) if (opts.method == "GET") { xhr.open( opts.method, opts.url + "?" + params_format(opts.data), opts.async ); xhr.send(); } else { xhr.open(opts.method, opts.url, opts.async); xhr.setRequestHeader("Content-Type", "application/x-www-form-urlencoded"); xhr.send(opts.data); } /*  ** 每当readyState改变时,就会触发onreadystatechange事件  ** readyState属性存储有XMLHttpRequest的状态信息  ** 0 :请求未初始化  ** 1 :服务器连接已建立  ** 2 :请求已接受  ** 3 : 请求处理中  ** 4 :请求已完成,且相应就绪  */ xhr.onreadystatechange = function () { if (xhr.readyState === 4 && (xhr.status === 200 || xhr.status === 304)) { switch (opts.dataType) { case "json": var json = JSON.parse(xhr.responseText); opts.success(json); break; case "xml": opts.success(xhr.responseXML); break; default: opts.success(xhr.responseText); break; } } }; xhr.onerror = function (err) { opts.error(err); }; }
  • JS接口安全域名不填写,分享onMenuShareAppMessage直接会取默认值。
// 分享onMenuShareAppMessage直接会取默认值
  • 关闭当前页面
WeixinJSBridge.call('closeWindow');
document.addEventListener('WeixinJSBridgeReady', function onBridgeReady(){ that.initOrder(); }, false);
  • 支付接口方法调用必须在
WeixinJSBridge.invoke('getBrandWCPayRequest', d, function(res){ if(res.err_msg == "get_brand_wcpay_request:ok"){ // alert("支付成功"); // union.release(d.orderId); resetUrl(); paySuccess('home', d.orderId); } else { cancelOrder(d.orderId); // alert(res.err_msg); } loading.hide(); });
  • 瀑布流无限加载实例
// be dependent on jquery & jquery.infinitescroll.min.js
// insert this '<div id="more"><a href="api?page="></a></div>' to your page.html
(function($){ $(function(){ var $container = $('.list-wrap-gd'); function layOutCallBack() { $container.imagesLoaded(function(){ $container.masonry({ itemSelector: '.item-bar', gutter: 10 }); }); $container.imagesLoaded().progress( function() { $container.masonry('layout'); }); } layOutCallBack(); $container.infinitescroll({ navSelector : "#more", nextSelector : "#more a", itemSelector : ".item-bar", pixelsFromNavToBottom: 300, loading:{ img: "/images/masonry_loading.gif", msgText: ' ', finishedMsg: "<em>已经到最后一页</em>", finished: function(){ $("#more").remove(); $("#infscr-loading").hide(); } }, errorCallback:function(){ $(window).unbind('.infscr'); }, pathParse: function (path, nextPage) { var query = ""; var keyword=$("#search_keyword").val(); var cat_id=$("#cat_id").val(); var brand_id=$("#brand_id").val(); var country_id = $("#country_id").val(); query = query + "&namekeyword="+keyword; query = query +"&cat_id="+cat_id query = query + "&brand_id=" + brand_id; query = query + "&country_id=" + country_id; path = [path,query]; return path; } }, function(newElements) { var $newElems = $( newElements ).css({ opacity: 0 }); $newElems.imagesLoaded(function(){ $newElems.animate({ opacity: 1 }); $container.masonry( 'appended', $newElems, true ); layOutCallBack(); }); }); }); })(jQuery);
if( /iPhone|iPod|iPad/i.test(navigator.userAgent) ) { $(document).on('focus', 'input, textarea', function() { $('header').css("position", 'absolute'); $('footer').css("position", 'absolute'); }); $(document).on('blur', 'input, textarea', function() { $('header').css("position", 'fixed'); $('footer').css("position", 'fixed'); }); } 
  • 得到地理位置
function getLocation(callback){
  if(navigator.geolocation){ navigator.geolocation.getCurrentPosition( function(p){ callback(p.coords.latitude, p.coords.longitude); }, function(e){ var msg = e.code + "\n" + e.message; } ); } }
(function(doc, win){
  var docEl = doc.documentElement, resizeEvt = 'orientationchange' in window ? 'orientationchange' : 'resize', recalc = function(){ var clientWidth = docEl.clientWidth; if(!clientWidth) return; docEl.style.fontSize = 20 * (clientWidth / 320) + 'px'; }; if(!doc.addEventListener) return; win.addEventListener(resizeEvt, recalc, false); doc.addEventListener('DOMContentLoaded', recalc, false); })(document, window);
var dpr, rem, scale;
var docEl = document.documentElement;
var fontEl = document.createElement('style'); var metaEl = document.querySelector('meta[name="viewport"]'); dpr = window.devicePixelRatio || 1; rem = docEl.clientWidth * 2 / 10; scale = 1 / dpr; // 设置viewport,进行缩放,达到高清效果 metaEl.setAttribute('content', 'width=' + dpr * docEl.clientWidth + ',initial-scale=' + scale + ',maximum-scale=' + scale + ', minimum-scale=' + scale + ',user-scalable=no'); // 设置data-dpr属性,留作的css hack之用 docEl.setAttribute('data-dpr', dpr); // 动态写入样式 docEl.firstElementChild.appendChild(fontEl); fontEl.innerHTML = 'html{font-size:' + rem + 'px!important;}'; // 给js调用的,某一dpr下rem和px之间的转换函数 window.rem2px = function(v) { v = parseFloat(v); return v * rem; }; window.px2rem = function(v) { v = parseFloat(v); return v / rem; }; window.dpr = dpr; window.rem = rem;
  • 获取js所在路径
function getJsDir (src) {
    var script = null; if (src) { script = [].filter.call(document.scripts, function (v) { return v.src.indexOf(src) !== -1; })[0]; } else { script = document.scripts[document.scripts.length - 1]; } return script ? script.src.substr(0, script.src.lastIndexOf('/')) : script; }
  • 页面加载自执行函数
function addload(func) {
  var old = window.onload; if (typeof window.onload != "function") { window.onload = func; } else { window.onload = function () { old(); func(); } } }
  • 从全局捕获错误
window.onerror = function (errMsg, scriptURI, lineNumber, columnNumber, errorObj) { setTimeout(function () { var rst = { "错误信息:": errMsg, "出错文件:": scriptURI, "出错行号:": lineNumber, "出错列号:": columnNumber, "错误详情:": errorObj }; alert(JSON.stringify(rst, null, 10)); }); };
var $body = $('body'); document.title = 'title'; // hack在微信等webview中无法修改document.title的情况 var $iframe = $('<iframe src="/favicon.ico"></iframe>').on('load', function(){ setTimeout(function(){ $iframe.off('load').remove() }, 0) }).appendTo($body)

1. 常用方法 - js

  • 字符串长度截取
function cutstr(str, len) {
    var temp,
        icount = 0, patrn = /[^\x00-\xff]/, strre = ""; for (var i = 0; i < str.length; i++) { if (icount < len - 1) { temp = str.substr(i, 1); if (patrn.exec(temp) == null) { icount = icount + 1 } else { icount = icount + 2 } strre += temp } else { break; } } return strre + "..." }
  • 替换全部
String.prototype.replaceAll = function(s1, s2) { return this.replace(new RegExp(s1, "gm"), s2) }
  • 清除空格
String.prototype.trim = function() {
    var reExtraSpace = /^\s*(.*?)\s+$/; return this.replace(reExtraSpace, "$1") }
  • 清除左空格/右空格
function ltrim(s){ return s.replace( /^(\s*| *)/, ""); } function rtrim(s){ return s.replace( /(\s*| *)$/, ""); }
  • 判断是否以某个字符串开头
String.prototype.startWith = function (s) { return this.indexOf(s) == 0 }
  • 判断是否以某个字符串结束
String.prototype.endWith = function (s) { var d = this.length - s.length; return (d >= 0 && this.lastIndexOf(s) == d) }
  • 转义html标签
function HtmlEncode(text) {
    return text.replace(/&/g, '&').replace(/\"/g, '"').replace(/</g, '<').replace(/>/g, '>') }
  • 时间日期格式转换
Date.prototype.Format = function(formatStr) { var str = formatStr; var Week = ['日', '一', '二', '三', '四', '五', '六']; str = str.replace(/yyyy|YYYY/, this.getFullYear()); str = str.replace(/yy|YY/, (this.getYear() % 100) > 9 ? (this.getYear() % 100).toString() : '0' + (this.getYear() % 100)); str = str.replace(/MM/, (this.getMonth() + 1) > 9 ? (this.getMonth() + 1).toString() : '0' + (this.getMonth() + 1)); str = str.replace(/M/g, (this.getMonth() + 1)); str = str.replace(/w|W/g, Week[this.getDay()]); str = str.replace(/dd|DD/, this.getDate() > 9 ? this.getDate().toString() : '0' + this.getDate()); str = str.replace(/d|D/g, this.getDate()); str = str.replace(/hh|HH/, this.getHours() > 9 ? this.getHours().toString() : '0' + this.getHours()); str = str.replace(/h|H/g, this.getHours()); str = str.replace(/mm/, this.getMinutes() > 9 ? this.getMinutes().toString() : '0' + this.getMinutes()); str = str.replace(/m/g, this.getMinutes()); str = str.replace(/ss|SS/, this.getSeconds() > 9 ? this.getSeconds().toString() : '0' + this.getSeconds()); str = str.replace(/s|S/g, this.getSeconds()); return str }
  • 判断日期是否有效
function isValidDate(value, userFormat='mm/dd/yyyy') { const delimiter = /[^mdy]/.exec(userFormat)[0]; const theFormat = userFormat.split(delimiter); const theDate = value.split(delimiter); function isDate(date, format) { let m, d, y, i = 0, len = format.length, f; for (i; i < len; i++) { f = format[i]; if (/m/.test(f)) m = date[i]; if (/d/.test(f)) d = date[i]; if (/y/.test(f)) y = date[i]; } return ( m > 0 && m < 13 && y && y.length === 4 && d > 0 && d <= (new Date(y, m, 0)).getDate() ); } return isDate(theDate, theFormat); }
  • 判断是否为数字类型
function isDigit(value) {
    var patrn = /^[0-9]*$/; if (patrn.exec(value) == null || value == "") { return false } else { return true } }
  • 判断具体类型
function getType(a) {
    var typeArray = Object.prototype.toString.call(a).split(" "); return typeArray[1].slice(0, -1); }
  • 设置cookie值
function setCookie(name, value, Hours) {
    var d = new Date(); var offset = 8; var utc = d.getTime() + (d.getTimezoneOffset() * 60000); var nd = utc + (3600000 * offset); var exp = new Date(nd); exp.setTime(exp.getTime() + Hours * 60 * 60 * 1000); document.cookie = name + "=" + escape(value) + ";path=/;expires=" + exp.toGMTString() + ";domain=360doc.com;" }
  • 获取cookie值
function getCookie(name) {
    var arr = document.cookie.match(new RegExp("(^| )" + name + "=([^;]*)(;|$)")); if (arr != null) return unescape(arr[2]); return null }
  • 加载样式文件表
function LoadStyle(url) {
    try {
        document.createStyleSheet(url) } catch(e) { var cssLink = document.createElement('link'); cssLink.rel = 'stylesheet'; cssLink.type = 'text/css'; cssLink.href = url; var head = document.getElementsByTagName('head')[0]; head.appendChild(cssLink) } }
  • 返回脚本内容
function evalscript(s) {
    if(s.indexOf('<script') == -1) return s; var p = /<script[^\>]*?>([^\x00]*?)<\/script>/ig; var arr = []; while(arr = p.exec(s)) { var p1 = /<script[^\>]*?src=\"([^\>]*?)\"[^\>]*?(reload=\"1\")?(?:charset=\"([\w\-]+?)\")?><\/script>/i; var arr1 = []; arr1 = p1.exec(arr[0]); if(arr1) { appendscript(arr1[1], '', arr1[2], arr1[3]); } else { p1 = /<script(.*?)>([^\x00]+?)<\/script>/i; arr1 = p1.exec(arr[0]); appendscript('', arr1[2], arr1[1].indexOf('reload=') != -1); } } return s; }
  • 清除脚本内容
function stripscript(s) {
    return s.replace(/<script.*?>.*?<\/script>/ig, ''); }
  • 动态加载脚本文件
function appendscript(src, text, reload, charset) { var id = hash(src + text); if(!reload && in_array(id, evalscripts)) return; if(reload && $(id)) { $(id).parentNode.removeChild($(id)); } evalscripts.push(id); var scriptNode = document.createElement("script"); scriptNode.type = "text/javascript"; scriptNode.id = id; scriptNode.charset = charset ? charset : (BROWSER.firefox ? document.characterSet : document.charset); try { if(src) { scriptNode.src = src; scriptNode.onloadDone = false; scriptNode.onload = function () { scriptNode.onloadDone = true; JSLOADED[src] = 1; }; scriptNode.onreadystatechange = function () { if((scriptNode.readyState == 'loaded' || scriptNode.readyState == 'complete') && !scriptNode.onloadDone) { scriptNode.onloadDone = true; JSLOADED[src] = 1; } }; } else if(text){ scriptNode.text = text; } document.getElementsByTagName('head')[0].appendChild(scriptNode); } catch(e) {} }
  • 动态加载js或css文件
function delay_js(url) {
  var type = url.split(".") , file = type[type.length - 1]; if (file == "css") { var obj = document.createElement("link") , lnk = "href" , tp = "text/css"; obj.setAttribute("rel", "stylesheet"); } else var obj = document.createElement("script") , lnk = "src" , tp = "text/javascript"; obj.setAttribute(lnk, url); obj.setAttribute("type", tp); file == "css" ? document.getElementsByTagName("head")[0].appendChild(obj) : document.body.appendChild(obj); return obj; }
  • 返回按ID检索的元素对象
function $(id) {
    return !id ? null : document.getElementById(id); }
  • 检验URL链接是否有效
function getUrlState(URL){ 
    var xmlhttp = new ActiveXObject("microsoft.xmlhttp"); xmlhttp.Open("GET",URL, false); try{ xmlhttp.Send(); }catch(e){ }finally{ var result = xmlhttp.responseText; if(result){ if(xmlhttp.Status==200){ return(true); }else{ return(false); } }else{ return(false); } } }
  • 获取当前路径
var currentPageUrl = "";
if (typeof this.href === "undefined") { currentPageUrl = document.location.toString().toLowerCase(); }else { currentPageUrl = this.href.toString().toLowerCase(); }
  • 获取页面高度
function getPageHeight(){
    var g = document, a = g.body, f = g.documentElement, d = g.compatMode == "BackCompat" ? a : g.documentElement; return Math.max(f.scrollHeight, a.scrollHeight, d.clientHeight); }
  • 获取页面可视宽度
function getPageViewWidth(){
    var d = document, a = d.compatMode == "BackCompat" ? d.body: d.documentElement; return a.clientWidth; }
  • 获取页面宽度
function getPageWidth(){
    var g = document, a = g.body, f = g.documentElement, d = g.compatMode == "BackCompat"? a: g.documentElement; return Math.max(f.scrollWidth, a.scrollWidth, d.clientWidth); }
  • 随机数时间戳
function uniqueId(){
    var a=Math.random,b=parseInt; return Number(new Date()).toString()+b(10*a())+b(10*a())+b(10*a()); }
  • 日期格式化函数
Date.prototype.format = function(format){ var o = { "M+" : this.getMonth()+1, //month "d+" : this.getDate(), //day "h+" : this.getHours(), //hour "m+" : this.getMinutes(), //minute "s+" : this.getSeconds(), //second "q+" : Math.floor((this.getMonth()+3)/3), //quarter "S" : this.getMilliseconds() //millisecond }; if(/(y+)/.test(format)) format=format.replace(RegExp.$1, (this.getFullYear()+"").substr(4 - RegExp.$1.length)); for(var k in o){ if(new RegExp("("+ k +")").test(format)) format = format.replace(RegExp.$1,RegExp.$1.length==1 ? o[k] :("00"+ o[k]).substr((""+ o[k]).length)); } return format; } //调用 //new Date().format("yyyy-MM-dd hh:mm:ss");
  • 返回顶部的通用方法
function backTop(btnId) {
    var btn = document.getElementById(btnId); var d = document.documentElement; var b = document.body; window.onscroll = set; btn.style.display = "none"; btn.onclick = function() { btn.style.display = "none"; window.onscroll = null; this.timer = setInterval(function() { d.scrollTop -= Math.ceil((d.scrollTop + b.scrollTop) * 0.1); b.scrollTop -= Math.ceil((d.scrollTop + b.scrollTop) * 0.1); if ((d.scrollTop + b.scrollTop) == 0) clearInterval(btn.timer, window.onscroll = set); }, 10); }; function set() { btn.style.display = (d.scrollTop + b.scrollTop > 100) ? 'block': "none" } }; backTop('goTop');
  • 获得URL中GET参数值
// 用法:如果地址是 test.htm?t1=1&t2=2&t3=3, 那么能取得:GET["t1"], GET["t2"], GET["t3"]
function get_get(){ 
    querystr = window.location.href.split("?") if(querystr[1]){ GETs = querystr[1].split("&"); GET = []; for(i=0;i<GETs.length;i++){ tmp_arr = GETs.split("=") key=tmp_arr[0] GET[key] = tmp_arr[1] } } return querystr[1]; }
  • 数组去重
String.prototype.unique=function(){
    var x=this.split(/[\r\n]+/); var y=''; for(var i=0;i<x.length;i++){ if(!new RegExp("^"+x.replace(/([^\w])/ig,"\\$1")+"$","igm").test(y)){ y+=x+"\r\n" } } return y };
  • 删除数组中某个元素
Array.prototype.remove = function (val) { var index = this.indexOf(val); if (index > -1) { this.splice(index, 1); } };
  • 判断数组里是否有某个元素
 Array.prototype.isContains = function (e) { for (i = 0; i < this.length && this[i] != e; i++); return !(i == this.length); }
  • 按字典顺序,对每行进行数组排序
function SetSort(){
    var text=K1.value.split(/[\r\n]/).sort().join("\r\n");//顺序 var test=K1.value.split(/[\r\n]/).sort().reverse().join("\r\n");//反序 K1.value=K1.value!=text?text:test; }
  • 字符串反序输出
function IsReverse(text){
    return text.split('').reverse().join(''); }
  • 金额大写转换函数
//格式转换
function transform(tranvalue) {
    try { var i = 1; var dw2 = new Array("", "万", "亿"); //大单位 var dw1 = new Array("拾", "佰", "仟"); //小单位 var dw = new Array("零", "壹", "贰", "叁", "肆", "伍", "陆", "柒", "捌", "玖"); //整数部分用 //以下是小写转换成大写显示在合计大写的文本框中 //分离整数与小数 var source = tranvalue.split("."); var num = source[0]; var dig = source[1]; //转换整数部分 var k1 = 0; //计小单位 var k2 = 0; //计大单位 var sum = 0; var str = ""; var len = source[0].length; //整数的长度 for (i = 1; i <= len; i++) { var n = source[0].charAt(len - i); //取得某个位数上的数字 var bn = 0; if (len - i - 1 >= 0) { bn = source[0].charAt(len - i - 1); //取得某个位数前一位上的数字 } sum = sum + Number(n); if (sum != 0) { str = dw[Number(n)].concat(str); //取得该数字对应的大写数字,并插入到str字符串的前面 if (n == '0') sum = 0; } if (len - i - 1 >= 0) { //在数字范围内 if (k1 != 3) { //加小单位 if (bn != 0) { str = dw1[k1].concat(str); } k1++; } else { //不加小单位,加大单位 k1 = 0; var temp = str.charAt(0); if (temp == "万" || temp == "亿") //若大单位前没有数字则舍去大单位 str = str.substr(1, str.length - 1); str = dw2[k2].concat(str); sum = 0; } } if (k1 == 3){ //小单位到千则大单位进一 k2++; } } //转换小数部分 var strdig = ""; if (dig != "") { var n = dig.charAt(0); if (n != 0) { strdig += dw[Number(n)] + "角"; //加数字 } var n = dig.charAt(1); if (n != 0) { strdig += dw[Number(n)] + "分"; //加数字 } } str += "元" + strdig; } catch(e) { return "0元"; } return str; }
  • 格式化数字
function fmoney(s, n) {
  //s:传入的float数字 ,n:希望返回小数点几位 n = n > 0 && n <= 20 ? n : 2; s = parseFloat((s + "").replace(/[^\d\.-]/g, "")).toFixed(n) + ""; var l = s .split(".")[0] .split("") .reverse(), r = s.split(".")[1]; t = ""; for (i = 0; i < l.length; i++) { t += l[i] + ((i + 1) % 3 == 0 && i + 1 != l.length ? "," : ""); } return; t .split("") .reverse() .join("") + "." + r; }
转载自:
https://github.com/jsfront/src/blob/master/js.md

猜你喜欢

转载自www.cnblogs.com/xuniannian/p/9889014.html