IDBKeyRange.includes()

Syntax

myIncludesResult = myKeyRange.includes('A');

Parameters

key

The key you want to check for in your key range. This can be any type.

Returns

A Boolean.

Exceptions

This method may raise a DOMException of the following type:

Example

var keyRangeValue = IDBKeyRange.bound('A', 'K', false, false);

var myResult = keyRangeValue.includes('F');
// Returns true

var myResult = keyRangeValue.includes('W');
// Returns false

Specification

Browser compatibility

Polyfill

The includes() method was added in the second edition of the Indexed DB specification. For browsers that do not support it, the following polyfill can be used.

IDBKeyRange.prototype.includes = IDBKeyRange.prototype.includes || function(key) {
  var r = this, c;
  if (r.lower !== undefined) {
    c = indexedDB.cmp(key, r.lower);
    if (r.lowerOpen && c <= 0) return false;
    if (!r.lowerOpen && c < 0) return false;
  }
  if (r.upper !== undefined) {
    c = indexedDB.cmp(key, r.upper);
    if (r.upperOpen && c >= 0) return false;
    if (!r.upperOpen && c > 0) return false;
  }
  return true;
};

See also

• Using IndexedDB
• Starting transactions: IDBDatabase
• Using transactions: IDBTransaction
• Setting a range of keys: IDBKeyRange
• Retrieving and making changes to your data: IDBObjectStore
• Using cursors: IDBCursor
• Reference example: To-do Notifications (view example live.)