getEntries()
方法在
PerformanceObserverEntryList
interface returns a list of explicitly
observed
performance entry
objects for a given filter. The list's members are determined by the set of
entry types
specified in the call to the
observe()
method. The list is available in the observer's callback function (as the first parameter in the callback).
This method is exposed to
Window
and
Worker
接口。
General syntax:
entries = list.getEntries(); entries = list.getEntries(PerformanceEntryFilterOptions);
Specific usage:
entries = list.getEntries({name: "entry_name", entryType: "mark"});
PerformanceEntryFilterOptions
可选
PerformanceEntryFilterOptions
字典,拥有以下字段:
"name"
, the name of a performance entry.
"entryType"
, the entry type. The valid entry types are listed in the
PerformanceEntry.entryType
方法。
"initiatorType"
, the type of the initiating resource (for example an HTML element). The values are defined by the
PerformanceResourceTiming.initiatorType
接口。
A list of explicitly
observed
PerformanceEntry
objects that meets the criteria of the filter. The items will be in chronological order based on the entries'
startTime
. If no objects that meet the filter are found, an empty list is returned. If no argument is given, all entries are returned.
function print_perf_entry(pe) {
console.log("name: " + pe.name +
"; entryType: " + pe.entryType +
"; startTime: " + pe.startTime +
"; duration: " + pe.duration);
}
// Create observer for all performance event types
var observe_all = new PerformanceObserver(function(list, obs) {
var perfEntries;
// Print all entries
perfEntries = list.getEntries();
for (var i=0; i < perfEntries.length; i++) {
print_perf_entry(perfEntries[i]);
}
// Print entries named "Begin" with type "mark"
perfEntries = list.getEntriesByName("Begin", "mark");
for (var i=0; i < perfEntries.length; i++) {
print_perf_entry(perfEntries[i]);
}
// Print entries with type "mark"
perfEntries = list.getEntriesByType("mark");
for (var i=0; i < perfEntries.length; i++) {
print_perf_entry(perfEntries[i]);
}
});
// subscribe to all performance event types
observe_all.observe({entryTypes: ['frame', 'mark', 'measure', 'navigation', 'resource', 'server']});
var observe_frame = new PerformanceObserver(function(list, obs) {
var perfEntries = list.getEntries();
// Should only have 'frame' entries
for (var i=0; i < perfEntries.length; i++) {
print_perf_entry(perfEntries[i]);
}
});
// subscribe to frame event only
observe_frame.observe({entryTypes: ['frame']});
| 规范 | 状态 | 注释 |
|---|---|---|
|
Performance Timeline Level 2
The definition of 'getEntries()' in that specification. |
候选推荐 | 初始定义。 |
| 桌面 | 移动 | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
getEntries
|
Chrome 52 | Edge ≤79 | Firefox 57 | IE No | Opera 39 | Safari No | WebView Android No | Chrome Android 52 | Firefox Android 57 | Opera Android 41 | Safari iOS No | Samsung Internet Android 6.0 |
完整支持
不支持
PerformanceObserverEntryList
getEntries()
getEntriesByName()
getEntriesByType()