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JS 参考

按类别分类的 JS 按字母顺序排列的 JS

JavaScript

JS 数组
Array[ ] Array( ) at() concat() constructor copyWithin() entries() every() fill() filter() find() findIndex() findLast() findLastIndex() flat() flatMap() forEach() from() includes() indexOf() isArray() join() keys() lastIndexOf() length map() of() pop() prototype push() reduce() reduceRight() reverse() shift() slice() some() sort() splice() toReversed() toSorted() toSpliced() toString() unshift() values() valueOf() with()
JS 布尔值
constructor prototype toString() valueOf()
JS 类
constructor() extends static super
JS 日期
new Date() constructor getDate() getDay() getFullYear() getHours() getMilliseconds() getMinutes() getMonth() getSeconds() getTime() getTimezoneOffset() getUTCDate() getUTCDay() getUTCFullYear() getUTCHours() getUTCMilliseconds() getUTCMinutes() getUTCMonth() getUTCSeconds() now() parse() prototype setDate() setFullYear() setHours() setMilliseconds() setMinutes() setMonth() setSeconds() setTime() setUTCDate() setUTCFullYear() setUTCHours() setUTCMilliseconds() setUTCMinutes() setUTCMonth() setUTCSeconds() toDateString() toISOString() toJSON() toLocaleDateString() toLocaleTimeString() toLocaleString() toString() toTimeString() toUTCString() UTC() valueOf()
JS 错误
name message
JS 全局
decodeURI() decodeURIComponent() encodeURI() encodeURIComponent() escape() eval() Infinity isFinite() isNaN() NaN Number() parseFloat() parseInt() String() undefined unescape()
JS JSON
parse() stringify()
JS 地图
new Map clear() delete() entries() forEach() get() groupBy() has() keys() set() size values()
JS 数学
abs() acos() acosh() asin() asinh() atan() atan2() atanh() cbrt() ceil() clz32() cos() cosh() E exp() expm1() floor() fround() LN2 LN10 log() log10() log1p() log2() LOG2E LOG10E max() min() PI pow() random() round() sign() sin() sinh() sqrt() SQRT1_2 SQRT2 tan() tanh() trunc()
JS 数字
constructor EPSILON isFinite() isInteger() isNaN() isSafeInteger() MAX_SAFE_INTEGER MIN_SAFE_INTEGER MAX_VALUE MIN_VALUE NaN NEGATIVE_INFINITY POSITIVE_INFINITY parseFloat() parseInt() prototype toExponential() toFixed() toLocaleString() toPrecision() toString() valueOf()
JS 对象
assign() constructor create() defineProperties() defineProperty() entries() freeze() fromEntries() getOwnPropertyDescriptor() getOwnPropertyDescriptors() getOwnPropertyNames() groupBy() isExtensible() isFrozen() isSealed() keys() preventExtensions() prototype seal() toString() valueOf() values()
JS 运算符 JS 优先级 JS Promise
all() allSettled() any() catch() finally() race() reject() resolve() then()
JS RegExp
修饰符: g i d m 组: [abc] [^abc] [0-9] [^0-9] (x|y) 元字符: . \w \W \d \D \s \S \b \B \0 \n \f \r \t \v \xxx \xdd \uxxxx 量词: + * ? {X} {X,Y} {X,} $ ^ ?= ?! 属性: constructor global ignoreCase lastIndex multiline source 方法: compile() exec() test() toString()
JS 集合
new Set add() clear() delete() entries() forEach() has() keys() size values()
JS 语句
break class const continue debugger do...while for for...in for...of function if...else let return switch throw try...catch var while
JS 字符串
at() charAt() charCodeAt() codePointAt() concat() constructor endsWith() fromCharCode() includes() indexOf() lastIndexOf() length localeCompare() match() padEnd() padStart() prototype repeat() replace() replaceAll() search() slice() split() startsWith() substr() substring() toLocaleLowerCase() toLocaleUpperCase() toLowerCase() toString() toUpperCase() trim() trimEnd() trimStart() valueOf()
JS TypedArray

窗口

窗口对象
addeventlistener() alert() atob() blur() btoa() clearInterval() clearTimeout() close() closed confirm() console defaultStatus document focus() frameElement frames history getComputedStyle() innerHeight innerWidth length localStorage location matchMedia() moveBy() moveTo() name navigator open() opener outerHeight outerWidth pageXOffset pageYOffset parent print() prompt() removeEventlistener() resizeBy() resizeTo() screen screenLeft screenTop screenX screenY scrollBy() scrollTo() scrollX scrollY sessionStorage self setInterval() setTimeout() status stop() top
窗口控制台
assert() clear() count() error() group() groupCollapsed() groupEnd() info() log() table() time() timeEnd() trace() warn()
窗口历史记录
back() forward() go() length
窗口位置
assign() hash host hostname href origin pathname port protocol reload() replace() search
窗口导航器
appCodeName appName appVersion cookieEnabled geolocation javaEnabled() language onLine platform product taintEnabled() userAgent
窗口屏幕
availHeight availWidth colorDepth height pixelDepth width

HTML DOM

HTML 文档
activeElement addEventListener() adoptNode() anchors applets baseURI body charset characterSet close() cookie createAttribute() createComment() createDocumentFragment() createElement() createEvent() createTextNode() defaultView designMode doctype documentElement documentMode documentURI domain domConfig embeds execCommand() forms getElementById() getElementsByClassName() getElementsByName() getElementsByTagName() hasFocus() head images implementation importNode() inputEncoding lastModified links normalize() normalizeDocument() open() querySelector() querySelectorAll() readyState referrer removeEventListener() renameNode() scripts strictErrorChecking title URL write() writeln()
HTML 元素
accessKey addEventListener() appendChild() attributes blur() childElementCount childNodes children classList className click() clientHeight clientLeft clientTop clientWidth cloneNode() closest() compareDocumentPosition() contains() contentEditable dir firstChild firstElementChild focus() getAttribute() getAttributeNode() getBoundingClientRect() getElementsByClassName() getElementsByTagName() hasAttribute() hasAttributes() hasChildNodes() id innerHTML innerText insertAdjacentElement() insertAdjacentHTML() insertAdjacentText() insertBefore() isContentEditable isDefaultNamespace() isEqualNode() isSameNode() isSupported() lang lastChild lastElementChild matches() namespaceURI nextSibling nextElementSibling nodeName nodeType nodeValue normalize() offsetHeight offsetWidth offsetLeft offsetParent offsetTop outerHTML outerText ownerDocument parentNode parentElement previousSibling previousElementSibling querySelector() querySelectorAll() remove() removeAttribute() removeAttributeNode() removeChild() removeEventListener() replaceChild() scrollHeight scrollIntoView() scrollLeft scrollTop scrollWidth setAttribute() setAttributeNode() style tabIndex tagName textContent title
HTML 属性
getNamedItem() isId item() length name removeNamedItem() setNamedItem() specified value
HTML 集合
item() length namedItem()
HTML 节点列表
entries() forEach() item() keys() length values()
HTML DOMTokenList
add() contains() entries() forEach() item() keys() length remove() replace() supports() toggle() value values()
HTML 样式
alignContent alignItems alignSelf animation animationDelay animationDirection animationDuration animationFillMode animationIterationCount animationName animationTimingFunction animationPlayState background backgroundAttachment backgroundClip backgroundColor backgroundImage backgroundOrigin backgroundPosition backgroundRepeat backgroundSize backfaceVisibility border borderBottom borderBottomColor borderBottomLeftRadius borderBottomRightRadius borderBottomStyle borderBottomWidth borderCollapse borderColor borderImage borderImageOutset borderImageRepeat borderImageSlice borderImageSource borderImageWidth borderLeft borderLeftColor borderLeftStyle borderLeftWidth borderRadius borderRight borderRightColor borderRightStyle borderRightWidth borderSpacing borderStyle borderTop borderTopColor borderTopLeftRadius borderTopRightRadius borderTopStyle borderTopWidth borderWidth bottom boxShadow boxSizing captionSide caretColor clear clip color columnCount columnFill columnGap columnRule columnRuleColor columnRuleStyle columnRuleWidth columns columnSpan columnWidth counterIncrement counterReset cssFloat cursor direction display emptyCells filter flex flexBasis flexDirection flexFlow flexGrow flexShrink flexWrap font fontFamily fontSize fontStyle fontVariant fontWeight fontSizeAdjust height isolation justifyContent left letterSpacing lineHeight listStyle listStyleImage listStylePosition listStyleType margin marginBottom marginLeft marginRight marginTop maxHeight maxWidth minHeight minWidth objectFit objectPosition opacity order orphans outline outlineColor outlineOffset outlineStyle outlineWidth overflow overflowX overflowY padding paddingBottom paddingLeft paddingRight paddingTop pageBreakAfter pageBreakBefore pageBreakInside perspective perspectiveOrigin position quotes resize right scrollBehavior tableLayout tabSize textAlign textAlignLast textDecoration textDecorationColor textDecorationLine textDecorationStyle textIndent textOverflow textShadow textTransform top transform transformOrigin transformStyle transition transitionProperty transitionDuration transitionTimingFunction transitionDelay unicodeBidi userSelect verticalAlign visibility width wordBreak wordSpacing wordWrap widows zIndex

HTML 事件

HTML 事件
abort afterprint animationend animationiteration animationstart beforeprint beforeunload blur canplay canplaythrough change click contextmenu copy cut dblclick drag dragend dragenter dragleave dragover dragstart drop durationchange ended error focus focusin focusout fullscreenchange fullscreenerror hashchange input invalid keydown keypress keyup load loadeddata loadedmetadata loadstart message mousedown mouseenter mouseleave mousemove mouseover mouseout mouseup offline online open pagehide pageshow paste pause play playing progress ratechange resize reset scroll search seeked seeking select show stalled submit suspend timeupdate toggle touchcancel touchend touchmove touchstart transitionend unload volumechange waiting wheel
HTML 事件对象
动画事件 剪贴板事件 拖放事件 事件 焦点事件 哈希值更改事件 输入事件 键盘事件 鼠标事件 页面过渡事件 历史记录状态变化事件 进度事件 存储事件 触摸事件 过渡事件 UI 事件 滚轮事件
HTML 事件属性
altKey (鼠标) altKey (键盘) animationName bubbles button buttons cancelable charCode clientX clientY code ctrlKey (鼠标) ctrlKey (键盘) currentTarget data defaultPrevented deltaX deltaY deltaZ deltaMode detail elapsedTime elapsedTime eventPhase inputType isTrusted key keyCode location metaKey (鼠标) metaKey (键盘) newURL oldURL offsetX offsetY pageX pageY persisted propertyName relatedTarget relatedTarget screenX screenY shiftKey (鼠标) shiftKey (键盘) target targetTouches timeStamp touches type which (鼠标) which (键盘) view
HTML 事件方法
getModifierState() preventDefault() stopImmidiatePropagation() stopPropagation()

Web API

API 画布 API 控制台 API 获取 API 全屏
exitFullscreen() fullscreenElement fullscreenEnabled() requestFullscreen()
API 地理位置
coordinates getCurrentPosition() position
API 历史记录 API 媒体查询列表 API 存储
clear() getItem() key() length removeItem() setItem()
API 验证 API 网页
crypto.getRandomNumber()

HTML 对象

<a> <abbr> <address> <area> <article> <aside> <audio> <b> <base> <bdo> <blockquote> <body> <br> <button> <canvas> <caption> <cite> <code> <col> <colgroup> <datalist> <dd> <del> <details> <dfn> <dialog> <div> <dl> <dt> <em> <embed> <fieldset> <figcaption> <figure> <footer> <form> <head> <header> <h1> - <h6> <hr> <html> <i> <iframe> <img> <ins> <input> button <input> checkbox <input> color <input> date <input> datetime <input> datetime-local <input> email <input> file <input> hidden <input> image <input> month <input> number <input> password <input> radio <input> range <input> reset <input> search <input> submit <input> text <input> time <input> url <input> week <kbd> <label> <legend> <li> <link> <map> <mark> <menu> <menuitem> <meta> <meter> <nav> <object> <ol> <optgroup> <option> <output> <p> <param> <pre> <progress> <q> <s> <samp> <script> <section> <select> <small> <source> <span> <strong> <style> <sub> <summary> <sup> <table> <tbody> <td> <tfoot> <th> <thead> <tr> <textarea> <time> <title> <track> <u> <ul> <var> <video>

其他参考

CSSStyleDeclaration
cssText getPropertyPriority() getPropertyValue() item() length parentRule removeProperty() setProperty()
JS 转换


onloadstart 事件

❮ 上一个 事件 参考 下一个 ❯

示例

视频开始加载时调用函数

<video onloadstart="myFunction()">
自己试一试 »

以下还有更多示例。

描述

当浏览器开始加载音频或视频时，会发生onloadstart 事件。

换句话说：当浏览器开始搜索音频或视频时。

音频和视频事件

加载媒体时，这些事件按以下顺序发生

事件发生时间
onloadstart开始加载媒体
ondurationchange媒体的时长已更改
onloadedmetadata媒体的元数据已加载
onloadeddata已加载媒体帧
onprogress浏览器正在加载媒体
oncanplay元素的滚动条正在滚动
oncanplaythrough浏览器估计它可以播放媒体
onplay媒体开始播放
onplaying媒体开始或恢复
ontimeupdate指示的时间已更改
onended媒体已播放到结尾

媒体加载或播放时可能发生的事件

事件发生时间
onabort媒体加载被中止
onemptied媒体为空（已加载）
onerror加载媒体时发生错误
onpause媒体已暂停
onratechange播放速度已更改
onseeked用户已搜索到新的媒体位置
onseeking用户开始搜索新的媒体位置
onstalled媒体数据不可用
onsuspend浏览器没有获取媒体数据
onvolumechange媒体的音量已更改
onwaiting媒体正在等待下一帧

另请参见

<audio> 对象
<video> 对象

语法

在 HTML 中

<element onloadstart="myScript">
自己试一试 »

在 JavaScript 中

object.onloadstart = function(){myScript};
自己试一试 »

在 JavaScript 中，使用 addEventListener() 方法

object.addEventListener("loadstart", myScript);
自己试一试 »

技术细节

冒泡 否
可取消 否
事件类型 ProgressEvent
HTML 标签 <audio> 和 <video>
DOM 版本 Level 3 Events

更多示例

示例

音频开始加载时调用函数

<audio onloadstart="myFunction()">
自己试一试 »

浏览器支持

onloadstart 是 DOM Level 3 (2004) 的功能。

它在所有现代浏览器中都得到完全支持

Chrome Edge Firefox Safari Opera IE
是 是 是 是 是 11


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