IDBKeyRange: lowerOpen property
Baseline Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
Note: This feature is available in Web Workers.
The lowerOpen read-only property of the IDBKeyRange interface returns a boolean indicating whether the lower-bound value is included in the key range.
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() { const keyRangeValue = IDBKeyRange.bound("F", "W", true, true); console.log(keyRangeValue.lowerOpen); const transaction = db.transaction(["fThings"], "readonly"); const objectStore = transaction.objectStore("fThings"); objectStore.openCursor(keyRangeValue).onsuccess = (event) => { const cursor = event.target.result; if (cursor) { const listItem = document.createElement("li"); listItem.textContent = `${cursor.value.fThing}, ${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
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 the example live).