WebSocket.onerror

The WebSocket.onerror property returns the event listener to be called when an error occurs. This is a simple event named "error".

在 WebSocket.onerror 属性中，你可以定义一个发生错误时执行的回调函数，此事件的事件名为"error"

WebSocket.onerror = function(event) {
  console.error("WebSocket error observed:", event);
};

An EventListener.