ProgressEvent | Web API

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构造函数
特性
方法
范例
规范
浏览器兼容性
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ProgressEvent interface represents events measuring progress of an underlying process, like an HTTP request (for an XMLHttpRequest , or the loading of the underlying resource of an <img> , <audio> , <video> , <style> or <link> ).

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  a:hover text { fill: #0095DD; pointer-events: all;}

构造函数

ProgressEvent(): 创建 ProgressEvent 事件采用给定参数。

特性

还继承特性从其父级 事件 .

ProgressEvent.lengthComputable 只读: 是 布尔 flag indicating if the total work to be done, and the amount of work already done, by the underlying process is calculable. In other words, it tells if the progress is measurable or not.
ProgressEvent.loaded 只读: 是 unsigned long long representing the amount of work already performed by the underlying process. The ratio of work done can be calculated with the property and ProgressEvent.total . When downloading a resource using HTTP, this only represent the part of the content itself, not headers and other overhead.
ProgressEvent.total 只读: 是 unsigned long long representing the total amount of work that the underlying process is in the progress of performing. When downloading a resource using HTTP, this only represent the content itself, not headers and other overhead.

方法

Also inherits methods from its parent 事件 .

ProgressEvent.initProgressEvent(): 初始化 ProgressEvent created using the deprecated Document.createEvent("ProgressEvent") 方法。

范例

The following example adds a ProgressEvent to a new XMLHTTPRequest and uses it to display the status of the request.

var progressBar = document.getElementById("p"),
    client = new XMLHttpRequest()
client.open("GET", "magical-unicorns")
client.onprogress = function(pe) {
  if(pe.lengthComputable) {
    progressBar.max = pe.total
    progressBar.value = pe.loaded
  }
}
client.onloadend = function(pe) {
  progressBar.value = pe.loaded
}
client.send()

规范

规范	状态	注释
XMLHttpRequest The definition of 'ProgressEvent' in that specification.	实时标准

浏览器兼容性

The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request. 更新 GitHub 上的兼容性数据

	桌面						移动
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
`ProgressEvent`	Chrome 1	Edge 12	Firefox 3.5	IE 10	Opera Yes	Safari Yes	WebView Android Yes	Chrome Android Yes	Firefox Android 4	Opera Android Yes	Safari iOS Yes	Samsung Internet Android Yes
`ProgressEvent()` 构造函数	Chrome Yes	Edge ≤79	Firefox 22	IE No	Opera Yes	Safari Yes	WebView Android Yes	Chrome Android Yes	Firefox Android 22	Opera Android Yes	Safari iOS Yes	Samsung Internet Android Yes
`initProgressEvent` 弃用非标	Chrome 1 — 17	Edge 12 — 79	Firefox 3.5 — 22	IE 10	Opera ? — 15	Safari ? — ?	WebView Android No	Chrome Android ? — ?	Firefox Android 4 — 22	Opera Android ? — 14	Safari iOS ? — ?	Samsung Internet Android No
`lengthComputable`	Chrome 50	Edge 12	Firefox 3.5	IE Yes	Opera 37	Safari 3.1	WebView Android 50	Chrome Android 50	Firefox Android 4	Opera Android 37	Safari iOS 2	Samsung Internet Android 5.0
`loaded`	Chrome Yes	Edge 12	Firefox 3.5	IE No	Opera Yes	Safari Yes	WebView Android Yes	Chrome Android Yes	Firefox Android 4	Opera Android Yes	Safari iOS Yes	Samsung Internet Android Yes
`total`	Chrome Yes	Edge 12	Firefox 3.5	IE No	Opera Yes	Safari Yes	WebView Android Yes	Chrome Android Yes	Firefox Android 4	Opera Android Yes	Safari iOS Yes	Samsung Internet Android Yes

图例

完整支持
不支持
非标。预期跨浏览器支持较差。
弃用。不要用于新网站。

另请参阅

事件 base interface.

元数据

最后修改： 2019 年 3 月 23 日

在此页

构造函数

特性

方法

范例

规范

浏览器兼容性

图例

另请参阅

相关话题