The lowerOpen read-only property of the IDBKeyRange interface returns a boolean indicating whether the lower-bound value is included in the key range.
Syntax
var lowerOpen = myKeyRange.lowerOpen
Value
A boolean:
| 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. |
Example
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.');
}
};
};
Specification
| Specification | Status | Comment |
|---|---|---|
| Indexed Database API 2.0 The definition of 'lowerOpen' in that specification. |
Recommendation | |
| Indexed Database API Draft The definition of 'lowerOpen' in that specification. |
Recommendation |
Browser compatibility
| Desktop | Mobile | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
lowerOpen | Chrome
Full support
24
| Edge Full support 12 | Firefox
Full support
16
| IE Partial support 10 | Opera Full support 15 | Safari Full support 7 | WebView Android Full support Yes | Chrome Android Full support Yes | Firefox Android Full support 22 | Opera Android Full support 14 | Safari iOS Full support 8 | Samsung Internet Android Full support Yes |
Legend
- Full support
- Full support
- Partial support
- Partial support
- Requires a vendor prefix or different name for use.
- Requires a vendor prefix or different name for use.
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.)
