已废弃
该特性已经从 Web 标准中删除,虽然一些浏览器目前仍然支持它,但也许会在未来的某个时间停止支持,请尽量不要使用该特性。
The deprecated 弃用context
所述的只读属性请求
接口包含请求的上下文(例如,audio
,image
,iframe
)。这定义了要获取的资源类型。它已由Request.destination”,“ destination
属性取代。 This defines what sort of resource is being fetched. This has been replaced by the destination
property.
The context of a request is only relevant in the 请求的上下文仅与ServiceWorker API相关;服务人员可以根据URL是用于图像还是可嵌入对象(例如<视频>
,iframe
等)进行决策。; a service worker can make decisions based on whether the URL is for an image, or an embeddable object such as a <video>
, iframe
, etc.
Note注意:您可以在“ 获取规范请求上下文”部分中找到不同可用上下文的完整列表,包括关联的上下文框架类型,CSP指令和平台功能示例。 section.
Syntax
var myContext = request.context;
Value
A RequestContext
value.一个RequestContext
值。
Example例子
In the following snippet, we create a new request using the Request.Request()
constructor (for an image file in the same directory as the script), then save the request context in a variable:在以下代码段中,我们使用Request.Request()
}构造函数创建一个新请求(用于与脚本位于同一目录中的图像文件),然后将请求上下文保存在变量中:
var myRequest = new Request('flowers.jpg');
var myContext = myRequest.context; // returns the empty string by default
Browser compatibility浏览器兼容性
BCD tables only load in the browser