The bound()
method of the IDBKeyRange
interface creates a new key range with 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.
Syntax
myKeyRange = IDBKeyRange.bound("A", "Z", true, true);
Returns
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:
|
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.'); } }; };
Parameters
- lower
- The lower bound of the key range.
- upper
- The upper bound of the key range.
- lowerOpen
- Optional. If false (default value), the range includes the lower bound value of the key range.
- upperOpen
- Optional. If false (default value), the range includes the upper bound value of the key range.
Specification
Specification | Status | Comment |
---|---|---|
Indexed Database API The definition of 'bound()' in that specification. |
Editor's Draft |
Browser compatibility
Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari (WebKit) |
---|---|---|---|---|---|
Basic support | 23webkit 24 |
10 moz 16.0 (16.0) |
10, partial | 15 | 7.1 |
Available in workers | (Yes) | 37.0 (37.0) | ? | (Yes) | ? |
Feature | Android | Firefox Mobile (Gecko) | Firefox OS | IE Phone | Opera Mobile | Safari Mobile |
---|---|---|---|---|---|---|
Basic support | 4.4 | 22.0 (22.0) | 1.0.1 | 10 | 22 | 8 |
Available in workers | (Yes) | 37.0 (37.0) | (Yes) | ? | (Yes) | ? |
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.)