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数组 Array
数组去重
function noRepeat(arr) {return [...new Set(arr)];
}查找数组最大
function arrayMax(arr) {return Math.max(...arr);
}查找数组最小
function arrayMin(arr) {return Math.min(...arr);
}返回已 size 为长度的数组宰割的原数组
function chunk(arr, size = 1) {
return Array.from(
{length: Math.ceil(arr.length / size),
},
(v, i) => arr.slice(i * size, i * size + size)
);
}查看数组中某元素呈现的次数
function countOccurrences(arr, value) {return arr.reduce((a, v) => (v === value ? a + 1 : a + 0), 0);
}扁平化数组
- 默认 depth 全副开展
function flatten(arr, depth = -1) {if (depth === -1) {return [].concat(...arr.map((v) => (Array.isArray(v) ? this.flatten(v) : v))
);
}
if (depth === 1) {return arr.reduce((a, v) => a.concat(v), []);
}
return arr.reduce((a, v) => a.concat(Array.isArray(v) ? this.flatten(v, depth - 1) : v),
[]);
}比照两个数组并且返回其中不同的元素
function diffrence(arrA, arrB) {return arrA.filter((v) => !arrB.includes(v));
}返回两个数组中雷同的元素
function intersection(arr1, arr2) {return arr2.filter((v) => arr1.includes(v));
}从右删除 n 个元素
function dropRight(arr, n = 0) {return n < arr.length ? arr.slice(0, arr.length - n) : [];}截取第一个符合条件的元素及其当前的元素
function dropElements(arr, fn) {while (arr.length && !fn(arr[0])) arr = arr.slice(1);
return arr;
}返回数组中下标距离 nth 的元素
function everyNth(arr, nth) {return arr.filter((v, i) => i % nth === nth - 1);
}返回数组中第 n 个元素
- 反对正数
function nthElement(arr, n = 0) {return (n >= 0 ? arr.slice(n, n + 1) : arr.slice(n))[0];
}返回数组头元素
function head(arr) {return arr[0];
}返回数组开端元素
function last(arr) {return arr[arr.length - 1];
}数组乱排
function shuffle(arr) {
let array = arr;
let index = array.length;
while (index) {
index -= 1;
let randomInedx = Math.floor(Math.random() * index);
let middleware = array[index];
array[index] = array[randomInedx];
array[randomInedx] = middleware;
}
return array;
}浏览器对象 BOM
判读浏览器是否反对 CSS 属性
/**
* 告知浏览器反对的指定 css 属性状况
* @param {String} key - css 属性，是属性的名字，不须要加前缀
* @returns {String} - 反对的属性状况
*/
function validateCssKey(key) {const jsKey = toCamelCase(key); // 有些 css 属性是连字符号造成
if (jsKey in document.documentElement.style) {return key;}
let validKey = "";
// 属性名为前缀在 js 中的模式，属性值是前缀在 css 中的模式
// 经尝试，Webkit 也可是首字母小写 webkit
const prefixMap = {
Webkit: "-webkit-",
Moz: "-moz-",
ms: "-ms-",
O: "-o-",
};
for (const jsPrefix in prefixMap) {const styleKey = toCamelCase(`${jsPrefix}-${jsKey}`);
if (styleKey in document.documentElement.style) {validKey = prefixMap[jsPrefix] + key;
break;
}
}
return validKey;
}
/**
* 把有连字符号的字符串转化为驼峰命名法的字符串
*/
function toCamelCase(value) {return value.replace(/-(\w)/g, (matched, letter) => {return letter.toUpperCase();
});
}
/**
* 查看浏览器是否反对某个 css 属性值（es6 版）* @param {String} key - 查看的属性值所属的 css 属性名
* @param {String} value - 要查看的 css 属性值（不要带前缀）* @returns {String} - 返回浏览器反对的属性值
*/
function valiateCssValue(key, value) {const prefix = ["-o-", "-ms-", "-moz-", "-webkit-", ""];
const prefixValue = prefix.map((item) => {return item + value;});
const element = document.createElement("div");
const eleStyle = element.style;
// 利用每个前缀的状况，且最初也要利用上没有前缀的状况，看最初浏览器起效的何种状况
// 这就是最好在 prefix 里的最初一个元素是 ''
prefixValue.forEach((item) => {eleStyle[key] = item;
});
return eleStyle[key];
}
/**
* 查看浏览器是否反对某个 css 属性值
* @param {String} key - 查看的属性值所属的 css 属性名
* @param {String} value - 要查看的 css 属性值（不要带前缀）* @returns {String} - 返回浏览器反对的属性值
*/
function valiateCssValue(key, value) {var prefix = ["-o-", "-ms-", "-moz-", "-webkit-", ""];
var prefixValue = [];
for (var i = 0; i < prefix.length; i++) {prefixValue.push(prefix[i] + value);
}
var element = document.createElement("div");
var eleStyle = element.style;
for (var j = 0; j < prefixValue.length; j++) {eleStyle[key] = prefixValue[j];
}
return eleStyle[key];
}
function validCss(key, value) {const validCss = validateCssKey(key);
if (validCss) {return validCss;}
return valiateCssValue(key, value);
}- 摘自 https://juejin.im/post/5e58f398f265da574a1eb569
返回以后网页地址
function currentURL() {return window.location.href;}获取滚动条地位
function getScrollPosition(el = window) {
return {
x: el.pageXOffset !== undefined ? el.pageXOffset : el.scrollLeft,
y: el.pageYOffset !== undefined ? el.pageYOffset : el.scrollTop,
};
}获取 url 中的参数
function getURLParameters(url) {
return url
.match(/([^?=&]+)(=([^&]*))/g)
.reduce((a, v) => ((a[v.slice(0, v.indexOf("="))] = v.slice(v.indexOf("=") + 1)), a
),
{});
}页面跳转，是否记录在 history 中
function redirect(url, asLink = true) {asLink ? (window.location.href = url) : window.location.replace(url);
}滚动条回到顶部动画
function scrollToTop() {
const scrollTop =
document.documentElement.scrollTop || document.body.scrollTop;
if (scrollTop > 0) {window.requestAnimationFrame(scrollToTop);
window.scrollTo(0, c - c / 8);
} else {window.cancelAnimationFrame(scrollToTop);
}
}复制文本
function copy(str) {const el = document.createElement("textarea");
el.value = str;
el.setAttribute("readonly", "");
el.style.position = "absolute";
el.style.left = "-9999px";
el.style.top = "-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);
}
}检测设施类型
function detectDeviceType() {
return /Android|webOS|iPhone|iPad|iPod|BlackBerry|IEMobile|Opera Mini/i.test(navigator.userAgent)
? "Mobile"
: "Desktop";
}Cookie
增
function setCookie(key, value, expiredays) {var exdate = new Date();
exdate.setDate(exdate.getDate() + expiredays);
document.cookie =
key +
"=" +
escape(value) +
(expiredays == null ? "":";expires=" + exdate.toGMTString());
}删
function delCookie(name) {var exp = new Date();
exp.setTime(exp.getTime() - 1);
var cval = getCookie(name);
if (cval != null) {document.cookie = name + "=" + cval + ";expires=" + exp.toGMTString();
}
}查
function getCookie(name) {
var arr,
reg = new RegExp("(^|)" + name + "=([^;]*)(;|$)");
if ((arr = document.cookie.match(reg))) {return arr[2];
} else {return null;}
}日期 Date
工夫戳转换为工夫
- 默认为以后工夫转换后果
- isMs 为工夫戳是否为毫秒
function timestampToTime(timestamp = Date.parse(new Date()), isMs = true) {const date = new Date(timestamp * (isMs ? 1 : 1000));
return `${date.getFullYear()}-${date.getMonth() + 1 < 10 ? "0" + (date.getMonth() + 1) : date.getMonth() + 1}-${date.getDate()} ${date.getHours()}:${date.getMinutes()}:${date.getSeconds()}`;
}文档对象 DOM
固定滚动条
/**
* 性能形容：一些业务场景，如弹框呈现时，须要禁止页面滚动，这是兼容安卓和 iOS 禁止页面滚动的解决方案
*/
let scrollTop = 0;
function preventScroll() {
// 存储以后滚动地位
scrollTop = window.scrollY;
// 将可滚动区域固定定位，可滚动区域高度为 0 后就不能滚动了
document.body.style["overflow-y"] = "hidden";
document.body.style.position = "fixed";
document.body.style.width = "100%";
document.body.style.top = -scrollTop + "px";
// document.body.style['overscroll-behavior'] = 'none'
}
function recoverScroll() {document.body.style["overflow-y"] = "auto";
document.body.style.position = "static";
// document.querySelector('body').style['overscroll-behavior'] = 'none'
window.scrollTo(0, scrollTop);
}判断以后地位是否为页面底部
- 返回值为 true/false
function bottomVisible() {
return (
document.documentElement.clientHeight + window.scrollY >=
(document.documentElement.scrollHeight ||
document.documentElement.clientHeight)
);
}判断元素是否在可视范畴内
- partiallyVisible 为是否为齐全可见
function elementIsVisibleInViewport(el, partiallyVisible = false) {const { top, left, bottom, right} = el.getBoundingClientRect();
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;
}获取元素 css 款式
function getStyle(el, ruleName) {return getComputedStyle(el, null).getPropertyValue(ruleName);
}进入全屏
function launchFullscreen(element) {if (element.requestFullscreen) {element.requestFullscreen();
} else if (element.mozRequestFullScreen) {element.mozRequestFullScreen();
} else if (element.msRequestFullscreen) {element.msRequestFullscreen();
} else if (element.webkitRequestFullscreen) {element.webkitRequestFullScreen();
}
}
launchFullscreen(document.documentElement);
launchFullscreen(document.getElementById("id")); // 某个元素进入全屏 退出全屏
function exitFullscreen() {if (document.exitFullscreen) {document.exitFullscreen();
} else if (document.msExitFullscreen) {document.msExitFullscreen();
} else if (document.mozCancelFullScreen) {document.mozCancelFullScreen();
} else if (document.webkitExitFullscreen) {document.webkitExitFullscreen();
}
}
exitFullscreen();全屏事件
document.addEventListener("fullscreenchange", function (e) {if (document.fullscreenElement) {console.log("进入全屏");
} else {console.log("退出全屏");
}
});数字 Number
数字千分位宰割
function commafy(num) {return num.toString().indexOf(".") !== -1
? num.toLocaleString()
: num.toString().replace(/(\d)(?=(?:\d{3})+$)/g, "$1,");
}生成随机数
function randomNum(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;
}
}交换
文章同步继续更新，往期文章收录在 https://github.com/Wscats/art…
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正文完
发表至： javascript
2021-07-21
