IDBKeyRange.bound()

The bound() method of the IDBKeyRange interface creates a new key range with the specified upper and lower bounds. The bounds can be open (that is, the bounds exclude the endpoint values) or closed (that is, the bounds include the endpoint values). By default, the bounds are closed.

Note: This feature is available in Web Workers.

Syntax

var myIDBKeyRange = IDBKeyRange.bound(lower, upper);
var myIDBKeyRange = IDBKeyRange.bound(lower, upper, lowerOpen);
var myIDBKeyRange = IDBKeyRange.bound(lower, upper, lowerOpen, upperOpen);

Parameters

lower 
specifies the lower bound of the new key range. 
upper 
specifies the upper bound of the new key range.
lowerOpen Optional
indicates whether the lower bound excludes the endpoint value. The default is false. 
upperOpen Optional
Indicates whether the upper bound excludes the endpoint value. The default is false. 

Return value

IDBKeyRange: The newly created key range.

Exceptions

This method may raise a DOMException of the following type:

Exception Description
DataError

The following conditions raise an exception:

  • The lower or upper parameters were not passed a valid key.
  • The lower key is greater than the upper key.
  • The lower key and upper key match and either of the bounds are open.

Example

The following example illustrates how you'd use a bound key range. Here we declare a keyRangeValue = IDBKeyRange.bound("A", "F"); — a range between values of "A" and "F". We open a transaction (using IDBTransaction) and an object store, and open a Cursor with IDBObjectStore.openCursor, declaring keyRangeValue as its optional key range value. This means that the cursor will only retrieve records with keys inside that range. This range includes the values "A" and "F", as we haven't declared that they should be open  bounds. If we used IDBKeyRange.bound("A", "F", true, true);, then the range would not include "A" and "F", only the values between them.

Note: For a more complete example allowing you to experiment with key range, have a look at our IDBKeyRange-example repo (view the example live too.)

function displayData() {
  var keyRangeValue = IDBKeyRange.bound("A", "F");

  var transaction = db.transaction(['fThings'], 'readonly');
  var objectStore = transaction.objectStore('fThings');

  objectStore.openCursor(keyRangeValue).onsuccess = function(event) {
    var cursor = event.target.result;
      if(cursor) {
        var listItem = document.createElement('li');
        listItem.innerHTML = '<strong>' + cursor.value.fThing + '</strong>, ' + cursor.value.fRating;
        list.appendChild(listItem);  
          
        cursor.continue();
      } else {
        console.log('Entries all displayed.');
      }
    };
  };

Specification

Browser compatibility

FeatureChromeEdgeFirefoxInternet ExplorerOperaSafari
Basic support

24

23 — 24 webkit

12

16

10 — 16 moz

101157
FeatureAndroid webviewChrome for AndroidEdge mobileFirefox for AndroidOpera AndroidiOS SafariSamsung Internet
Basic support Yes Yes Yes22228 Yes

1. partial

See also

Document Tags and Contributors

Last updated by: fscholz,