我們的志工尚未將此文章翻譯為 正體中文 (繁體) 版本。加入我們，幫忙翻譯！
The unhandledrejection event is fired when a JavaScript Promise is rejected but there is no rejection handler to deal with the rejection.
| Bubbles | No |
| Cancelable | No |
| Target objects | defaultView |
| Interface | PromiseRejectionEvent |
Examples
window.addEventListener("unhandledrejection", function (event) {
console.warn("WARNING: Unhandled promise rejection. Shame on you! Reason: "
+ event.reason);
});
Inheritance
The unhandledrejection event implements the PromiseRejectionEvent interface, which inherits from Event. You can use the properties and methods defined on these interfaces.
<div id="interfaceDiagram" style="display: inline-block; position: relative; width: 100%; padding-bottom: 11.666666666666666%; vertical-align: middle; overflow: hidden;"><svg style="display: inline-block; position: absolute; top: 0; left: 0;" viewbox="-50 0 600 70" preserveAspectRatio="xMinYMin meet"><a xlink:href="https://developer.mozilla.org/en-US/docs/Web/API/Event" target="_top"><rect x="1" y="1" width="75" height="50" fill="#fff" stroke="#D4DDE4" stroke-width="2px" /><text x="38.5" y="30" font-size="12px" font-family="Consolas,Monaco,Andale Mono,monospace" fill="#4D4E53" text-anchor="middle" alignment-baseline="middle">Event</text></a><polyline points="76,25 86,20 86,30 76,25" stroke="#D4DDE4" fill="none"/><line x1="86" y1="25" x2="116" y2="25" stroke="#D4DDE4"/><a xlink:href="https://developer.mozilla.org/en-US/docs/Web/API/PromiseRejectionEvent" target="_top"><rect x="116" y="1" width="210" height="50" fill="#F4F7F8" stroke="#D4DDE4" stroke-width="2px" /><text x="221" y="30" font-size="12px" font-family="Consolas,Monaco,Andale Mono,monospace" fill="#4D4E53" text-anchor="middle" alignment-baseline="middle">PromiseRejectionEvent</text></a></svg></div>
a:hover text { fill: #0095DD; pointer-events: all;}