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JS 参考手册

JS 参考手册（类别排序） JS 参考手册（字母排序）

JavaScript

JS Array
concat() constructor copyWithin() entries() every() fill() filter() find() findIndex() forEach() from() includes() indexOf() isArray() join() keys() length lastIndexOf() map() pop() prototype push() reduce() reduceRight() reverse() shift() slice() some() sort() splice() toString() unshift() valueOf()
JS Boolean
constructor prototype toString() valueOf()
JS Classes
constructor() extends static super
JS 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 Error
name message
JS Global
decodeURI() decodeURIComponent() encodeURI() encodeURIComponent() escape() eval() Infinity isFinite() isNaN() NaN Number() parseFloat() parseInt() String() undefined unescape()
JS JSON
parse() stringify()
JS Math
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() sqrt() SQRT1_2 SQRT2 tan() tanh() trunc()
JS Number
constructor isFinite() isInteger() isNaN() isSafeInteger() MAX_VALUE MIN_VALUE NEGATIVE_INFINITY NaN POSITIVE_INFINITY prototype toExponential() toFixed() toLocaleString() toPrecision() toString() valueOf()
JS 运算符 JS RegExp
constructor compile() exec() g global i ignoreCase lastIndex m multiline n+ n* n? n{X} n{X,Y} n{X,} n$ ^n ?=n ?!n source test() toString() [abc] [^abc] [0-9] [^0-9] (x|y) . \w \W \d \D \s \S \b \B \0 \n \f \r \t \v \xxx \xdd \uxxxx
JS 语句
break class continue debugger do...while for for...in for...of function if...else return switch throw try...catch var while
JS String
charAt() charCodeAt() concat() constructor endsWith() fromCharCode() includes() indexOf() lastIndexOf() length localeCompare() match() prototype repeat() replace() search() slice() split() startsWith() substr() substring() toLocaleLowerCase() toLocaleUpperCase() toLowerCase() toString() toUpperCase() trim() valueOf()

HTML DOM

DOM Attributes
getNamedItem() isId item() length name removeNamedItem() setNamedItem() specified value
DOM Document
activeElement addEventListener() adoptNode() anchors applets baseURI body close() cookie charset characterSet createAttribute() createComment() createDocumentFragment() createElement() createEvent() createTextNode() defaultView designMode doctype documentElement documentMode documentURI domain embeds execCommand() forms fullscreenElement fullscreenEnabled() 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()
DOM Element
accessKey addEventListener() appendChild() attributes blur() childElementCount childNodes children classList className click() clientHeight clientLeft clientTop clientWidth cloneNode() closest() compareDocumentPosition() contains() contentEditable dir exitFullscreen() 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() requestFullscreen() scrollHeight scrollIntoView() scrollLeft scrollTop scrollWidth setAttribute() setAttributeNode() style tabIndex tagName textContent title
DOM Events
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 altKey altKey animationName bubbles button buttons cancelable charCode clientX clientY code createEvent() ctrlKey ctrlKey currentTarget data defaultPrevented deltaX deltaY deltaZ deltaMode detail elapsedTime elapsedTime eventPhase getModifierState() inputType isTrusted key keyCode location metaKey metaKey newURL oldURL pageX pageY persisted preventDefault() propertyName relatedTarget relatedTarget screenX screenY shiftKey shiftKey stopImmediatePropagation() stopPropagation() target targetTouches timeStamp touches type which which view
DOM Event 对象
AnimationEvent ClipboardEvent DragEvent Event FocusEvent HashChangeEvent InputEvent KeyboardEvent MouseEvent PageTransitionEvent PopStateEvent ProgressEvent StorageEvent TouchEvent TransitionEvent UiEvent WheelEvent
DOM HTMLCollection
item() length namedItem()
DOM Location
hash host hostname href origin pathname port protocol search assign() reload() replace()
DOM Navigator
appCodeName appName appVersion cookieEnabled geolocation language onLine platform product userAgent javaEnabled() taintEnabled()
DOM Screen
availHeight availWidth colorDepth height pixelDepth width
DOM Style
alignContent alignItems alignSelf animation animationDelay animationDirection animationDuration animationFillMode animationIterationCount animationName animationTimingFunction animationPlayState background backgroundAttachment backgroundColor backgroundImage backgroundPosition backgroundRepeat backgroundClip backgroundOrigin 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 cursor direction display emptyCells filter flex flexBasis flexDirection flexFlow flexGrow flexShrink flexWrap cssFloat 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
DOM Window
closed console defaultStatus document frameElement frames history innerHeight innerWidth length localStorage location name navigator opener outerHeight outerWidth pageXOffset pageYOffset parent screen screenLeft screenTop screenX screenY sessionStorage self status top alert() atob() blur() btoa() clearInterval() clearTimeout() close() confirm() focus() getComputedStyle() matchMedia() moveBy() moveTo() open() print() prompt() resizeBy() resizeTo() scrollBy() scrollTo() setInterval() setTimeout() stop()

Web APIs

API Console
assert() clear() count() error() group() groupCollapsed() groupEnd() info() log() table() time() timeEnd() trace() warn()
API Geolocation
coordinates position
API History
back() forward() go() length
API Storage
key() length getItem() setItem() removeItem() clear()

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>

其他参考手册

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


Source media 属性

❮ Source 对象

实例

返回特定文件优化的媒体/设备:

var x = document.getElementById("mySource").media;
亲自试一试 »

定义和用法

media 属性设置或返回 <source> 元素中 media 属性的值。

媒体属性指定媒体资源的类型（文件优化的媒体/设备）。

浏览器可以使用媒体属性来判断是否可以播放文件。 如果不能，它可以选择不下载。

浏览器支持

属性
media Yes Yes Yes Yes Yes

注释: 但是，任何主流浏览器都不支持 HTML media 属性。

语法

返回 media 属性:

sourceObject.media

设置 media 属性:

sourceObject.media = value

注释: This property can accept several values.

Possible Operators

值 描述
and 指定 AND 运算符
not 指定 NOT 运算符
, 指定 OR 运算符

设备

值 描述
all 适用于所有设备。 这是默认的
aural 语音合成器
braille 盲文反馈装置
handheld 手持设备（小屏幕，有限带宽）
projection 投影仪
print 打印预览模式/打印页面
screen 电脑屏幕
tty 使用固定间距字符网格的电传打字机和类似媒体
tv 电视类型的设备（低分辨率，有限的滚动能力）

值

值 描述
width 指定目标显示区域的宽度。
可以使用 "min-" 和 "max-" 前缀。
示例: media="screen and (min-width:500px)"
height 指定目标显示区域的高度。
可以使用 "min-" 和 "max-" 前缀。
示例: media="screen and (max-height:700px)"
device-width 指定目标显示器/纸张的宽度。
可以使用 "min-" 和 "max-" 前缀。
示例: media="screen and (device-width:500px)"
device-height 指定目标显示器/纸张的高度。
可以使用 "min-" 和 "max-" 前缀。
示例: media="screen and (device-height:500px)"
orientation 指定目标显示器/纸张的方向。
可能的值为: "portrait" 或 "landscape"
示例: media="all and (orientation: landscape)"
aspect-ratio 指定目标显示区域的宽高比。
可以使用 "min-" 和 "max-" 前缀。
示例: media="screen and (aspect-ratio:16/9)"
device-aspect-ratio 指定目标显示器/纸张的设备宽度/设备高度比率。
可以使用 "min-" 和 "max-" 前缀。
示例: media="screen and (aspect-ratio:16/9)"
color 指定目标显示器每种颜色的位数。
可以使用 "min-" 和 "max-" 前缀。
示例: media="screen and (color:3)"
color-index 指定目标显示器可以处理的颜色数量。
可以使用 "min-" 和 "max-" 前缀。
示例: media="screen and (min-color-index:256)"
monochrome 指定单色帧缓冲区中每个像素的位数。
可以使用 "min-" 和 "max-" 前缀。
示例: media="screen and (monochrome:2)"
resolution 指定目标显示器/纸张的像素密度（dpi 或 dpcm）。
可以使用 "min-" 和 "max-" 前缀。
示例: media="print and (resolution:300dpi)"
scan 指定电视显示器的扫描方法。
可能的值为 "progressive" 和 "interlace".
示例: media="tv and (scan:interlace)"
grid 指定输出设备是网格还是位图。
可能的值为 "1" for grid, and "0" otherwise.
示例: media="handheld and (grid:1)"

技术细节

返回值: 字符串，表示媒体资源的缩进类型

相关页面

HTML 参考手册: HTML <source> media 属性

❮ Source 对象