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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 正则表达式
修饰符: g i d m 分组: [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 类型化数组

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
后退() 前进() go() 长度
窗口位置
assign() 哈希 主机 主机名 href 来源 路径名 端口 协议 重新加载() 替换() 搜索
窗口导航器
应用程序代码名 应用程序名 应用程序版本 CookieEnabled 地理位置 javaEnabled() 语言 在线 平台 产品 taintEnabled() 用户代理
窗口屏幕
可用高度 可用宽度 颜色深度 高度 像素深度 宽度

HTML DOM

HTML 文档
活动元素 addEventListener() adoptNode() 锚点 小程序 基本 URI 正文 字符集 字符集 关闭() Cookie createAttribute() createComment() createDocumentFragment() createElement() createEvent() createTextNode() 默认视图 设计模式 文档类型 文档元素 文档模式 文档 URI 域 domConfig 嵌入 execCommand() 表单 getElementById() getElementsByClassName() getElementsByName() getElementsByTagName() hasFocus() 头部 图像 实现 importNode() 输入编码 最后修改时间 链接 规范化() 规范化文档() 打开() querySelector() querySelectorAll() 就绪状态 来源 removeEventListener() renameNode() 脚本 严格错误检查 标题 URL 写入() writeln()
HTML 元素
访问键 addEventListener() appendChild() 属性 blur() 子元素数量 子节点 子元素 classList 类名 点击() clientHeight clientLeft clientTop clientWidth cloneNode() closest() compareDocumentPosition() contains() contentEditable 方向 第一个子节点 第一个子元素 focus() getAttribute() getAttributeNode() getBoundingClientRect() getElementsByClassName() getElementsByTagName() hasAttribute() hasAttributes() hasChildNodes() ID innerHTML innerText insertAdjacentElement() insertAdjacentHTML() insertAdjacentText() insertBefore() isContentEditable isDefaultNamespace() isEqualNode() isSameNode() isSupported() 语言 最后一个子节点 最后一个子元素 matches() 命名空间 URI 下一个兄弟节点 下一个兄弟元素 节点名称 节点类型 节点值 规范化() offsetHeight offsetWidth offsetLeft offsetParent offsetTop outerHTML outerText 拥有文档 父节点 父元素 上一个兄弟节点 上一个兄弟元素 querySelector() querySelectorAll() 移除() removeAttribute() removeAttributeNode() removeChild() removeEventListener() replaceChild() scrollHeight scrollIntoView() scrollLeft scrollTop scrollWidth setAttribute() setAttributeNode() 样式 tabIndex 标签名 textContent 标题
HTML 属性
getNamedItem() isId item() 长度 名称 removeNamedItem() setNamedItem() 已指定 值
HTML 集合
item() 长度 namedItem()
HTML 节点列表
entries() forEach() item() keys() 长度 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 哈希变化事件 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 用户界面事件 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


选项 selected 属性

❮ 选项对象

示例

将下拉列表中的选中选项更改为“orange”

document.getElementById("orange").selected = true;
尝试一下 »

描述

selected 属性设置或返回选项的选中状态。

浏览器支持

属性
selected 是 是 是 是 是

语法

返回 selected 属性

optionObject.selected

设置 selected 属性

optionObject.selected = true|false

属性值

值 描述
true|false 指定下拉列表中的选项是否应选中。
  • true - 选项已选中
  • false - 默认。选项未选中

技术细节

返回值 布尔值，如果选项已选中则返回 true，否则返回 false

更多示例

示例

找出下拉列表中的“banana”选项是否已选中

var x = document.getElementById("banana").selected;
尝试一下 »

相关页面

HTML 参考：HTML <option> selected 属性

❮ 选项对象
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