IDBKeyRange: upperBound() static method
The upperBound()
static method of the
IDBKeyRange
interface creates a new upper-bound key range. By default,
it includes the upper endpoint value and is closed.
Note: This feature is available in Web Workers
Syntax
js
IDBKeyRange.upperBound(upper)
IDBKeyRange.upperBound(upper, open)
Parameters
upper
-
Specifies the upper bound of the new key range.
open
Optional-
Indicates whether the upper bound excludes the endpoint value. The default is false.
Return value
IDBKeyRange
: The newly created key range.
Exceptions
DataError
DOMException
-
Thrown if the key associated with the
upper
parameter is not a valid key.
Examples
The following example illustrates how you'd use an upper bound key range. Here we
declare keyRangeValue = IDBKeyRange.upperBound("F");
— a range that
includes the value "F" and everything before it. 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.
If we used IDBKeyRange.upperBound("F", true);
, then the range excludes
"F"; and instead only includes the values before it.
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.)
js
function displayData() {
const keyRangeValue = IDBKeyRange.upperBound("F");
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-upperbound① |
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 the example live).