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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 JS 布尔值 JS 类 JS 日期 JS 错误 JS 全局 JS JSON JS 映射 JS 数学 JS 数字 JS 对象 JS 运算符 JS 优先级 JS Promises JS 正则表达式 JS 集合 JS 语句 JS 字符串 JS TypedArray

窗口

窗口对象 窗口控制台 窗口历史记录 窗口位置 窗口导航器 窗口屏幕

HTML DOM

HTML 文档 HTML 元素 HTML 属性 HTML 集合 HTML 节点列表 HTML DOMTokenList 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 HTML 事件对象 HTML 事件属性 HTML 事件方法

Web APIs

API Canvas API Console API Fetch API 全屏 API Geolocation API History API MediaQueryList API Storage API Validation API Web

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 JS 转换


输入日期时间 required 属性

❮ 输入日期时间对象

示例

找出在提交表单之前是否必须填写日期时间字段

var x = document.getElementById("myDatetime").required;
亲自试一试 »

描述

required 属性设置或返回日期时间字段是否必须在提交表单之前填写。

此属性反映 HTML required 属性。


浏览器支持

属性
required 10.0

注意:<input type="datetime"> 元素在除 Safari 之外的所有主要浏览器中均不显示任何日期时间字段/日历。


语法

返回 required 属性

datetimeObject.required

设置 required 属性

datetimeObject.required = true|false

属性值

描述
true|false 指定日期时间字段是否应为表单提交的必填部分。
  • true - 日期时间字段是表单提交的必填部分
  • false - 默认值。日期时间字段不是表单提交的必填部分

技术细节

返回值 布尔值,如果日期时间字段是表单提交的必填部分,则返回 true,否则返回 false

更多示例

示例

将日期时间字段设置为表单提交的必填部分

document.getElementById("myDatetime").required = true;
亲自试一试 »

相关页面

HTML 参考:HTML <input> required 属性


❮ 输入日期时间对象
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