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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

var isIncluded = myKeyRange.includes(key)

Parameters

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

Return value

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

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;
};

Specification

Specification Status Comment
Indexed Database API 2.0
The definition of 'includes()' in that specification.
Recommendation  
Indexed Database API 2.0
The definition of 'includes()' in that specification.
Recommendation  

Browser compatibility

FeatureChromeEdgeFirefoxInternet ExplorerOperaSafari
Basic support52 Yes47 ?3910.1
FeatureAndroid webviewChrome for AndroidEdge mobileFirefox for AndroidOpera AndroidiOS SafariSamsung Internet
Basic support5252 Yes ?3910.16.0

See also

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