Node.js PerformanceObserverEntryList.getEntriesByType(type)用法及代碼示例

performanceObserverEntryList.getEntriesByType(type)

參數

• type <string>
• 返回： <PerformanceEntry[]>

根據 performanceEntry.startTime 的時間順序返回 PerformanceEntry 對象的列表，其 performanceEntry.entryType 等於 type 。

const {
  performance,
  PerformanceObserver
} = require('node:perf_hooks');

const obs = new PerformanceObserver((perfObserverList, observer) => {
  console.log(perfObserverList.getEntriesByType('mark'));
  /**
   * [
   *   PerformanceEntry {
   *     name: 'test',
   *     entryType: 'mark',
   *     startTime: 55.897834,
   *     duration: 0
   *   },
   *   PerformanceEntry {
   *     name: 'meow',
   *     entryType: 'mark',
   *     startTime: 56.350146,
   *     duration: 0
   *   }
   * ]
   */
  performance.clearMarks();
  performance.clearMeasures();
  observer.disconnect();
});
obs.observe({ type: 'mark' });

performance.mark('test');
performance.mark('meow');