IDBKeyRange.lowerOpen
The lowerOpen read-only property of the
IDBKeyRange interface returns a boolean indicating whether the
lower-bound value is included in the key range.
Note: This feature is available in Web Workers
Value
A boolean value:
| Value | Indication |
|---|---|
true |
The lower-bound value is not included in the key range. |
false |
The lower-bound value is included in the key range. |
Examples
The following example illustrates how you'd use a key range. Here we
declare keyRangeValue = IDBKeyRange.upperBound("F", "W", true, true); — a
range that includes everything between "F" and "W" but not including them — since both
the upper and lower bounds have been declared as open (true). 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.
After declaring the key range, we log its lowerOpen property value to the
console, which should appear as "true": the lower bound is open, so won't be included in
the range.
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("F", "W", true, true);
console.log(keyRangeValue.lowerOpen);
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.');
}
};
};
Specifications
| Specification |
|---|
| Indexed Database API 3.0 # ref-for-dom-idbkeyrange-loweropen① |
Browser compatibility
BCD tables only load in the browser
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.)