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PerformanceEntry.entryType - Web APIs 编辑

The entryType property returns a DOMString representing the type of performance metric such as, for example, "mark". This property is read only.

Note:

This feature is available in Web Workers.

Syntax

var type = entry.entryType;

Return value

The return value depends on the subtype of the PerformanceEntry object and affects the value of the PerformanceEntry.name property as shown by the table below.

Performance entry type names

Value	Subtype	Type of name property	Description of name property
`frame`, `navigation`	`PerformanceFrameTiming`, `PerformanceNavigationTiming`	`URL`	The document's address.
`resource`	`PerformanceResourceTiming`	`URL`	The resolved URL of the requested resource. This value doesn't change even if the request is redirected.
`mark`	`PerformanceMark`	`DOMString`	The name used when the mark was created by calling `performance.mark()`.
`measure`	`PerformanceMeasure`	`DOMString`	name used when the measure was created by calling `performance.measure()`.
`paint`	`PerformancePaintTiming`	`DOMString`	Either `'first-paint'` or `'first-contentful-paint'`.
`longtask`	`PerformanceLongTaskTiming`	`DOMString`	reports instances of long tasks

Example

The following example shows the use of the entryType property.

function run_PerformanceEntry() {

  // check for feature support before continuing
  if (performance.mark === undefined) {
    console.log("performance.mark not supported");
    return;
  }

  // Create a performance entry named "begin" via the mark() method
  performance.mark("begin");

  // Check the entryType of all the "begin" entries
  var entriesNamedBegin = performance.getEntriesByName("begin");
	for (var i=0; i < entriesNamedBegin.length; i++) {
      var typeOfEntry = entriesNamedBegin[i].entryType;
      console.log("Entry is type: " + typeOfEntry);
  }

}

Specifications

Specification	Status	Comment
Performance Timeline Level 2 The definition of 'entryType' in that specification.	Candidate Recommendation
Performance Timeline The definition of 'entryType' in that specification.	Recommendation	Initial definition.