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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 JS 类型转换


Input Email defaultValue 属性

❮ Input Email 对象

实例

更改电子邮件字段的默认值:

document.getElementById("myEmail").defaultValue = "steve@www.w3ccoo.com";
亲自试一试 »

定义和用法

defaultValue 属性设置或返回电子邮件字段的默认值。

注释:默认值是 HTML value 属性中指定的值。

defaultValue 和 value 属性的区别在于 defaultValue 包含默认值,而 value 包含经过一些更改后的当前值。 如果没有更改,则 defaultValue 和 value 相同(请参阅下面的"更多示例")。

当您想了解电子邮件字段是否已更改时,defaultValue 属性很有用。


浏览器支持

属性
defaultValue Yes 10.0 Yes Yes Yes

语法

返回 defaultValue 属性:

emailObject.defaultValue

设置 defaultValue 属性:

emailObject.defaultValue = value

属性值

描述
value 指定电子邮件字段的默认值


技术细节

返回值: 字符串,代表email字段的默认值

更多实例

实例

获取电子邮件字段的默认值:

var x = document.getElementById("myEmail").defaultValue;
亲自试一试 »

实例

一个展示defaultValue和value属性区别的例子:

var x = document.getElementById("myEmail");
var defaultVal = x.defaultValue;
var currentVal = x.value;
亲自试一试 »

❮ Input Email 对象