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/DOM

IDBKeyRange.includes

The includes() method of the IDBKeyRange interface returns a boolean indicating whether a specified key is inside the key range.

Note: This feature is available in Web Workers.

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:

Attribute	Description
`DataError`	The supplied key was not a valid key.

Example

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

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

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

Specification

Specification	Status	Comment
Indexed Database API (Second Edition) The definition of 'includes()' in that specification.	Recommendation

Browser compatibility

Feature	Chrome	Firefox (Gecko)	Internet Explorer	Opera	Safari (WebKit)
`includes()`	52.0	47.0 (47.0)	?	39	?

Feature	Android	Android Webview	Firefox Mobile (Gecko)	Firefox OS	IE Phone	Opera Mobile	Safari Mobile	Chrome for Android
`includes()`	No support	52.0	?	?	?	39	?	52.0

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;
};