The fetchStart
read-only property represents a timestamp
immediately before the browser starts to fetch the resource.
If there are HTTP redirects the property returns the time immediately before the user agent starts to fetch the final resource in the redirection.
A DOMHighResTimeStamp
immediately before the browser starts to fetch the resource.
In the following example, the value of the *Start
and *End
properties of all "resource
" type
events are logged.
function print_PerformanceEntries() {
var p = performance.getEntriesByType("resource");
for (var i=0; i < p.length; i++) {
print_start_and_end_properties(p[i]);
}
}
function print_start_and_end_properties(perfEntry) {
properties = ["connectStart", "connectEnd",
"domainLookupStart", "domainLookupEnd",
"fetchStart",
"redirectStart", "redirectEnd",
"requestStart",
"responseStart", "responseEnd",
"secureConnectionStart"];
for (var i=0; i < properties.length; i++) {
var supported = properties[i] in perfEntry;
if (supported) {
var value = perfEntry[properties[i]];
console.log("... " + properties[i] + " = " + value);
} else {
console.log("... " + properties[i] + " = NOT supported");
}
}
}