PerformanceTiming

PerformanceTiming インターフェイスは、下位互換性のために維持されている従来のインターフェイスであり、現在のページのロード中および使用中に発生するさまざまなイベントに関するパフォーマンスタイミング情報を提供するプロパティを含みます。window.performance.timing プロパティを使用して、ページを記述する PerformanceTiming オブジェクトを取得します。

The PerformanceTiming interface doesn't inherit any properties.

These properties each describe the time at which a particular point in the page loading process was reached. Some correspond to DOM events; others describe the time at which internal browser operations of interest took place.

Each time is provided as an unsigned long long representing the moment, in milliseconds since the UNIX epoch

These properties are listed in the order in which they occur during the navigation process.

PerformanceTiming.navigationStart 読取専用

When the prompt for unload terminates on the previous document in the same browsing context. If there is no previous document, this value will be the same as PerformanceTiming.fetchStart.

PerformanceTiming.unloadEventStart 読取専用

When the unload event has been thrown, indicating the time at which the previous document in the window began to unload. If there is no previous document, or if the previous document or one of the needed redirects is not of the same origin, the value returned is 0.

  PerformanceTiming.unloadEventEnd 読取専用

When the unload event handler finishes. If there is no previous document, or if the previous document, or one of the needed redirects, is not of the same origin, the value returned is 0.

  PerformanceTiming.redirectStart 読取専用

When the first HTTP redirect starts. If there is no redirect, or if one of the redirects is not of the same origin, the value returned is 0.

  PerformanceTiming.redirectEnd 読取専用

When the last HTTP redirect is completed, that is when the last byte of the HTTP response has been received. If there is no redirect, or if one of the redirects is not of the same origin, the value returned is 0.

  PerformanceTiming.fetchStart 読取専用

When the browser is ready to fetch the document using an HTTP request. This moment is before the check to any application cache.

  PerformanceTiming.domainLookupStart 読取専用

When the domain lookup starts. If a persistent connection is used, or the information is stored in a cache or a local resource, the value will be the same as PerformanceTiming.fetchStart.

  PerformanceTiming.domainLookupEnd 読取専用

When the domain lookup is finished. If a persistent connection is used, or the information is stored in a cache or a local resource, the value will be the same as PerformanceTiming.fetchStart.

  PerformanceTiming.connectStart 読取専用

When the request to open a connection is sent to the network. If the transport layer reports an error and the connection establishment is started again, the last connection establishment start time is given. If a persistent connection is used, the value will be the same as PerformanceTiming.fetchStart.

  PerformanceTiming.connectEnd 読取専用

When the connection is opened network. If the transport layer reports an error and the connection establishment is started again, the last connection establishment end time is given. If a persistent connection is used, the value will be the same as PerformanceTiming.fetchStart. A connection is considered as opened when all secure connection handshake, or SOCKS authentication, is terminated.

  PerformanceTiming.secureConnectionStart 読取専用

When the secure connection handshake starts. If no such connection is requested, it returns 0.

  PerformanceTiming.requestStart 読取専用

When the browser sent the request to obtain the actual document, from the server or from a cache. If the transport layer fails after the start of the request and the connection is reopened, this property will be set to the time corresponding to the new request.

  PerformanceTiming.responseStart 読取専用

When the browser received the first byte of the response, from the server from a cache, or from a local resource.

  PerformanceTiming.responseEnd 読取専用

When the browser received the last byte of the response, or when the connection is closed if this happened first, from the server, the cache, or from a local resource.

  PerformanceTiming.domLoading 読取専用

When the parser started its work, that is when its Document.readyState changes to 'loading' and the corresponding readystatechange event is thrown.

  PerformanceTiming.domInteractive 読取専用

When the parser finished its work on the main document, that is when its Document.readyState changes to 'interactive' and the corresponding readystatechange event is thrown.

  PerformanceTiming.domContentLoadedEventStart 読取専用

Right before the parser sent the DOMContentLoaded event, that is right after all the scripts that need to be executed right after parsing have been executed.

  PerformanceTiming.domContentLoadedEventEnd 読取専用

Right after all the scripts that need to be executed as soon as possible, in order or not, have been executed.

  PerformanceTiming.domComplete 読取専用

When the parser finished its work on the main document, that is when its Document.readyState changes to 'complete' and the corresponding readystatechange event is thrown.

  PerformanceTiming.loadEventStart 読取専用

When the load event was sent for the current document. If this event has not yet been sent, it returns 0.

  PerformanceTiming.loadEventEnd 読取専用

When the load event handler terminated, that is when the load event is completed. If this event has not yet been sent, or is not yet completed, it returns 0.

The PerformanceTiming interface doesn't inherit any methods.

  PerformanceTiming.toJSON()

Returns a JSON object representing this PerformanceTiming object.

• The Performance.timing property that creates such an object.