前端业务中比较常用的JavaScript工具函数,浏览器环境常用,可直接拷贝在项目里使用。这里统一整理,方便查阅,本文章会持续更新。一、file转为base64一、file转为base64
/**
* file转为base64
* @param {*} file file对象
* @param {*} callback
*/
export const fileToDataURL = (file, callback) => {
let freader = new FileReader();
freader.readAsDataURL(file);
freader.onload = function (e) { callback(e.target.result); }
}
/**
* file转为base64
* @param {*} file file对象
* @param {*} callback
*/
export const fileToDataURL = (file, callback) => {
let freader = new FileReader();
freader.readAsDataURL(file);
freader.onload = function (e) { callback(e.target.result); }
}二、blob流转换为base64二、blob流转换为base64
/**
* blob流转换为base64
* @param {*} blob blob对象
* @param {*} callback
*/
export const blobToDataURL = (blob, callback) => {
let freader = new FileReader();
freader.readAsDataURL(blob);
freader.onload = function (e) { callback(e.target.result); }
}
/**
* blob流转换为base64
* @param {*} blob blob对象
* @param {*} callback
*/
export const blobToDataURL = (blob, callback) => {
let freader = new FileReader();
freader.readAsDataURL(blob);
freader.onload = function (e) { callback(e.target.result); }
}三、base64转换为blob三、base64转换为blob
/**
* base64转换为blob
* @param {*} dataurl base64
*/
export const dataURLtoBlob = (dataurl) => {
let arr = dataurl.split(','),

mime = arr[0].match(/:(.*?);/)[1],

bstr = atob(arr[1]),

n = bstr.length,

u8arr = new Uint8Array(n);
while (n--) {

u8arr[n] = bstr.charCodeAt(n);
}
return new Blob([u8arr], { type: mime });
}
/**
* base64转换为blob
* @param {*} dataurl base64
*/
export const dataURLtoBlob = (dataurl) => {
let arr = dataurl.split(','),

mime = arr[0].match(/:(.*?);/)[1],

bstr = atob(arr[1]),

n = bstr.length,

u8arr = new Uint8Array(n);
while (n--) {

u8arr[n] = bstr.charCodeAt(n);
}
return new Blob([u8arr], { type: mime });
}四、base64转换为file,IE低版本不兼容四、base64转换为file,IE低版本不兼容
/**
* 将base64转换为file,IE低版本不兼容
* @param {*} dataurl base64
* @param {*} filename 文件名
*/
export const dataURLtoFile = (dataurl, filename) => {
let arr = dataurl.split(','),

mime = arr[0].match(/:(.*?);/)[1],

bstr = atob(arr[1]),

n = bstr.length,

u8arr = new Uint8Array(n);
while (n--) {

u8arr[n] = bstr.charCodeAt(n);
}
return new File([u8arr], filename, { type: mime });
}
/**
* 将base64转换为file,IE低版本不兼容
* @param {*} dataurl base64
* @param {*} filename 文件名
*/
export const dataURLtoFile = (dataurl, filename) => {
let arr = dataurl.split(','),

mime = arr[0].match(/:(.*?);/)[1],

bstr = atob(arr[1]),

n = bstr.length,

u8arr = new Uint8Array(n);
while (n--) {

u8arr[n] = bstr.charCodeAt(n);
}
return new File([u8arr], filename, { type: mime });
}五、图片url转化成base64五、图片url转化成base64
/**
* 图片url转化成base64
* @param {*} url 图片url
* @param {*} callback
* @param {*} outputFormat 图片格式
*/
export const imgUrlToDataURL = (url, callback, outputFormat) => {

let canvas = document.createElement('canvas'),

ctx = canvas.getContext('2d'),

img = new Image;

img.crossOrigin = 'Anonymous';

img.src = url + "?timeStamp=" + new Date().getTime();

img.onload = function () {

canvas.height = img.height;

canvas.width = img.width;

// ctx.drawImage(img, 0, 0);

ctx.drawImage(this, 0, 0, img.width, img.height);

let dataURL = canvas.toDataURL(outputFormat || 'image/png');

// callback.call(this, dataURL);

callback && callback(dataURL)

canvas = null;

};
}
/**
* 图片url转化成base64
* @param {*} url 图片url
* @param {*} callback
* @param {*} outputFormat 图片格式
*/
export const imgUrlToDataURL = (url, callback, outputFormat) => {

let canvas = document.createElement('canvas'),

ctx = canvas.getContext('2d'),

img = new Image;

img.crossOrigin = 'Anonymous';

img.src = url + "?timeStamp=" + new Date().getTime();

img.onload = function () {

canvas.height = img.height;

canvas.width = img.width;

// ctx.drawImage(img, 0, 0);

ctx.drawImage(this, 0, 0, img.width, img.height);

let dataURL = canvas.toDataURL(outputFormat || 'image/png');

// callback.call(this, dataURL);

callback && callback(dataURL)

canvas = null;

};
}六、获取窗口尺寸六、获取窗口尺寸
export function getViewportSize() {
let w = 0;
let h = 0;
if (window.innerWidth) {

w = window.innerWidth

h = window.innerHeight
} else if (document.body && document.body.clientWidth) {

w = document.body.clientWidth

h = document.body.clientHeight
} else if (document.documentElement && document.documentElement.clientWidth) {

w = document.documentElement.clientWidth

h = document.documentElement.clientHeight
}
return { w, h }
}
export function getViewportSize() {
let w = 0;
let h = 0;
if (window.innerWidth) {

w = window.innerWidth

h = window.innerHeight
} else if (document.body && document.body.clientWidth) {

w = document.body.clientWidth

h = document.body.clientHeight
} else if (document.documentElement && document.documentElement.clientWidth) {

w = document.documentElement.clientWidth

h = document.documentElement.clientHeight
}
return { w, h }
}七、浏览器环境检测七、浏览器环境检测
const ua = window.navigator.userAgent.toLowerCase()

// 是否微信
export const isWx = () => ua.match(/MicroMessenger/i) == 'micromessenger'

// 是否ipad
export const isIpad = () => ua.indexOf('ipad') > -1

// 是否iphone
export const isIphone = () => ua.indexOf('iphone os') > -1

// 是否uc
export const isUc = () => ua.indexOf('ucweb') > -1

// 是否windows pc
export const isWindows = () => ua.indexOf('windows') > -1

// 是否android
export const isAndroid = () => ua.indexOf('android') > -1 || ua.indexOf('adr') > -1

// 是否ios
export const isIos = () => /(iphone|ipod|ipad|ios)/i.test(ua)

// 是否qq浏览器
export const isQq = () => ua.indexOf('mqqbrowser') > -1 && ua.indexOf(' qq') < 0

// 是否qq内置浏览器
export const isQQInstalled = () => ua.indexOf(' qq') > -1 && ua.indexOf('mqqbrowser') < 0
const ua = window.navigator.userAgent.toLowerCase()

// 是否微信
export const isWx = () => ua.match(/MicroMessenger/i) == 'micromessenger'

// 是否ipad
export const isIpad = () => ua.indexOf('ipad') > -1

// 是否iphone
export const isIphone = () => ua.indexOf('iphone os') > -1

// 是否uc
export const isUc = () => ua.indexOf('ucweb') > -1

// 是否windows pc
export const isWindows = () => ua.indexOf('windows') > -1

// 是否android
export const isAndroid = () => ua.indexOf('android') > -1 || ua.indexOf('adr') > -1

// 是否ios
export const isIos = () => /(iphone|ipod|ipad|ios)/i.test(ua)

// 是否qq浏览器
export const isQq = () => ua.indexOf('mqqbrowser') > -1 && ua.indexOf(' qq') < 0

// 是否qq内置浏览器
export const isQQInstalled = () => ua.indexOf(' qq') > -1 && ua.indexOf('mqqbrowser') < 0八、开启与关闭全屏八、开启与关闭全屏
// 开启全屏
export function launchFullscreen(element) {
element = element || document.documentElement
if (element.requestFullscreen) {

element.requestFullscreen()
} else if (element.mozRequestFullScreen) {

element.mozRequestFullScreen()
} else if (element.msRequestFullscreen) {

element.msRequestFullscreen()
} else if (element.webkitRequestFullscreen) {

element.webkitRequestFullScreen()
}
}

// 关闭全屏
export 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()
}
}
// 开启全屏
export function launchFullscreen(element) {
element = element || document.documentElement
if (element.requestFullscreen) {

element.requestFullscreen()
} else if (element.mozRequestFullScreen) {

element.mozRequestFullScreen()
} else if (element.msRequestFullscreen) {

element.msRequestFullscreen()
} else if (element.webkitRequestFullscreen) {

element.webkitRequestFullScreen()
}
}

// 关闭全屏
export 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()
}
}九、返回顶部/指定位置,实现滚动动画九、返回顶部/指定位置,实现滚动动画
/**
* @param {*} number 距离页面顶部的距离
* @param {*} time 滚动所需时间 单位ms
*/
const scrolling = (number = 0, time) => {

if (!time) {

document.body.scrollTop = document.documentElement.scrollTop = number;

return number;

}

// 设置循环的间隔时间 值越小消耗性能越高

const spacingTime = 20;

// 计算循环的次数

let spacingInex = time / spacingTime;

// 获取当前滚动条位置

let nowTop = document.body.scrollTop + document.documentElement.scrollTop;

// 计算每次滑动的距离

let everTop = (number - nowTop) / spacingInex;


let scrollTimer = setInterval(() => {

if (spacingInex > 0) {

spacingInex--;

ScrollTop(nowTop += everTop);

} else {

clearInterval(scrollTimer); // 清除计时器

}

}, spacingTime);
};

// 滚动到距离页面顶部500px的位置 动画时间为300ms
// scrolling(500, 300);
/**
* @param {*} number 距离页面顶部的距离
* @param {*} time 滚动所需时间 单位ms
*/
const scrolling = (number = 0, time) => {

if (!time) {

document.body.scrollTop = document.documentElement.scrollTop = number;

return number;

}

// 设置循环的间隔时间 值越小消耗性能越高

const spacingTime = 20;

// 计算循环的次数

let spacingInex = time / spacingTime;

// 获取当前滚动条位置

let nowTop = document.body.scrollTop + document.documentElement.scrollTop;

// 计算每次滑动的距离

let everTop = (number - nowTop) / spacingInex;


let scrollTimer = setInterval(() => {

if (spacingInex > 0) {

spacingInex--;

ScrollTop(nowTop += everTop);

} else {

clearInterval(scrollTimer); // 清除计时器

}

}, spacingTime);
};

// 滚动到距离页面顶部500px的位置 动画时间为300ms
// scrolling(500, 300);十、实现锚点滚动十、实现锚点滚动
// 运用了H5的scrollIntoView方法,这是一个实验中的功能,IE 8以下、Safari 6以下、Safari on iOS 5以下不兼容
const scrollToAnchor = (anchorName) => {

if (anchorName) {

// 找到锚点

let anchorElement = document.getElementById(anchorName);

// 如果对应id的锚点存在,就跳转到锚点

if (anchorElement) {

anchorElement.scrollIntoView({

behavior: 'auto', // 定义动画过渡效果, "auto"或 "smooth" 之一。默认为 "auto"

block: 'start', // 定义垂直方向的对齐, "start", "center", "end", 或 "nearest"之一。默认为 "start"

inline: 'nearest', // 定义水平方向的对齐, "start", "center", "end", 或 "nearest"之一。默认为 "nearest"

});

}

}
}
// 运用了H5的scrollIntoView方法,这是一个实验中的功能,IE 8以下、Safari 6以下、Safari on iOS 5以下不兼容
const scrollToAnchor = (anchorName) => {

if (anchorName) {

// 找到锚点

let anchorElement = document.getElementById(anchorName);

// 如果对应id的锚点存在,就跳转到锚点

if (anchorElement) {

anchorElement.scrollIntoView({

behavior: 'auto', // 定义动画过渡效果, "auto"或 "smooth" 之一。默认为 "auto"

block: 'start', // 定义垂直方向的对齐, "start", "center", "end", 或 "nearest"之一。默认为 "start"

inline: 'nearest', // 定义水平方向的对齐, "start", "center", "end", 或 "nearest"之一。默认为 "nearest"

});

}

}
}以上就是JavaScript常用工具函数汇总(浏览器环境)的详细内容,关于JavaScript 工具函数的资料请关注其它相关文章!