The only() method of the IDBKeyRange interface creates a new key range containing a single value.
var myIDBKeyRange = IDBKeyRange.only(value);
value is the value for the new key range.
IDBKeyRange: The newly created key range.
This method may raise a DOMException of the following types:
| Exception | Description |
|---|---|
| DataError | The value parameter passed was not a valid key. |
The following example illustrates how you'd use an only key range. Here we declare a keyRangeValue = IDBKeyRange.only("A"); — a range that only includes the value "A". 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 the record with the key value "A".
Note: For a more complete example allowing you to experiment with key range, have a look at our IDBKeyRange repo (view the example live too.)
function displayData() {
var keyRangeValue = IDBKeyRange.only("A");
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 | Status | Comment |
|---|---|---|
| Indexed Database API The definition of 'only' in that specification. | Recommendation | |
| Indexed Database API 2.0 The definition of 'only' in that specification. | Recommendation |
| Desktop | ||||||
|---|---|---|---|---|---|---|
| Chrome | Edge | Firefox | Internet Explorer | Opera | Safari | |
| Basic support | 24
|
12 | 16
|
10
|
15 | 7 |
| Mobile | |||||||
|---|---|---|---|---|---|---|---|
| Android webview | Chrome for Android | Edge Mobile | Firefox for Android | Opera for Android | iOS Safari | Samsung Internet | |
| Basic support | Yes | Yes | Yes | 22 | 22 | 8 | Yes |
IDBDatabase
IDBTransaction
IDBKeyRange
IDBObjectStore
IDBCursor
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Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/API/IDBKeyRange/only