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IDBDatabase: close event

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since ⁨January 2020⁩.

The close event is fired on IDBDatabase when the database connection is unexpectedly closed. This could happen, for example, if the underlying storage is removed or if the user clears the database in the browser's history preferences.

Note that it is not fired if the database connection is closed normally using IDBDatabase.close().

Syntax

Use the event name in methods like addEventListener(), or set an event handler property.

addEventListener("close", (event) => { })

onclose = (event) => { }

Event type

A generic Event.

Examples

This example opens a database and listens for the close event:

// Open the database
const dBOpenRequest = window.indexedDB.open("toDoList", 4);

dBOpenRequest.onupgradeneeded = (event) => {
  const db = event.target.result;

  // Create an objectStore for this database
  const objectStore = db.createObjectStore("toDoList", {
    keyPath: "taskTitle",
  });

  // define what data items the objectStore will contain
  objectStore.createIndex("hours", "hours", { unique: false });
  objectStore.createIndex("minutes", "minutes", { unique: false });
  objectStore.createIndex("day", "day", { unique: false });
  objectStore.createIndex("month", "month", { unique: false });
  objectStore.createIndex("year", "year", { unique: false });
};

dBOpenRequest.onsuccess = (event) => {
  const db = dBOpenRequest.result;
  db.addEventListener("close", () => {
    console.log("Database connection closed");
  });
};

The same example, using the onclose property instead of addEventListener():

// Open the database
const dBOpenRequest = window.indexedDB.open("toDoList", 4);

dBOpenRequest.onupgradeneeded = (event) => {
  const db = event.target.result;

  // Create an objectStore for this database
  const objectStore = db.createObjectStore("toDoList", {
    keyPath: "taskTitle",
  });

  // define what data items the objectStore will contain
  objectStore.createIndex("hours", "hours", { unique: false });
  objectStore.createIndex("minutes", "minutes", { unique: false });
  objectStore.createIndex("day", "day", { unique: false });
  objectStore.createIndex("month", "month", { unique: false });
  objectStore.createIndex("year", "year", { unique: false });
};

dBOpenRequest.onsuccess = (event) => {
  const db = dBOpenRequest.result;
  db.onclose = () => {
    console.log("Database connection closed");
  };
};

Specifications

Specification
Indexed Database API 3.0> # closing-connection>
Indexed Database API 3.0> # dom-idbdatabase-onclose>

Browser compatibility