From 33058f2b292b3a581333bdfb21b8f671898c5060 Mon Sep 17 00:00:00 2001 From: Peter Bengtsson Date: Tue, 8 Dec 2020 14:40:17 -0500 Subject: initial commit --- .../web/api/document/visibilitystate/index.html | 52 ++++++++++++++++++++++ 1 file changed, 52 insertions(+) create mode 100644 files/zh-cn/web/api/document/visibilitystate/index.html (limited to 'files/zh-cn/web/api/document/visibilitystate') diff --git a/files/zh-cn/web/api/document/visibilitystate/index.html b/files/zh-cn/web/api/document/visibilitystate/index.html new file mode 100644 index 0000000000..40cde7513b --- /dev/null +++ b/files/zh-cn/web/api/document/visibilitystate/index.html @@ -0,0 +1,52 @@ +--- +title: Document.visibilityState +slug: Web/API/Document/visibilityState +translation_of: Web/API/Document/visibilityState +--- +

{{ ApiRef("DOM") }}

+ +

 Document.visibilityState (只读属性), 返回{{domxref('document')}}的可见性, 即当前可见元素的上下文环境. 由此可以知道当前文档(即为页面)是在背后, 或是不可见的隐藏的标签页,或者(正在)预渲染.可用的值如下:

+ + + +

当此属性的值改变时, 会递交 {{event('visibilitychange')}} 事件给{{domxref("Document")}}.

+ +

典型用法是防止当页面正在渲染时加载资源, 或者当页面在背景中或窗口最小化时禁止某些活动.

+ +

语法

+ +
var string = document.visibilityState
+ +

示例

+ +
document.addEventListener("visibilitychange", function() {
+  console.log( document.visibilityState );
+  // Modify behavior...
+});
+ +

规范

+ + + + + + + + + + + + + + +
SpecificationStatusComment
{{SpecName('Page Visibility API','#dom-document-visibilitystate', 'Document.visibilityState')}}{{Spec2('Page Visibility API')}}Initial definition.
+ +

浏览器兼容性

+ + + +

{{Compat("api.Document.visibilityState")}}

-- cgit v1.2.3-54-g00ecf