SharedStorage: append() method
Limited availability
This feature is not Baseline because it does not work in some of the most widely-used browsers.
Experimental: This is an experimental technology
Check the Browser compatibility table carefully before using this in production.
The append()
method of the SharedStorage
interface appends a string to the value of an existing key-value pair in the current origin's shared storage.
Syntax
append(key, value)
Parameters
key
-
A string representing the key of the key-value pair to which you want to append a value.
value
-
A string that you want to append to the existing value of the key-value pair.
Note:
If the specified key
isn't found in the shared storage, the append()
operation is equivalent to set()
, that is, a new key-value pair with the specified key
is added to the shared storage.
Return value
A Promise
that fulfills with undefined
.
Exceptions
- The
Promise
rejects with aTypeError
if:- The appended entry was not successfully stored in the database due to shared storage not being available (for example it is disabled using a browser setting).
key
and/orvalue
exceed the browser-defined maximum length.- The calling site does not have the Shared Storage API included in a successful privacy sandbox enrollment process.
- In the case of
WorkletSharedStorage
, thePromise
rejects with aTypeError
if the worklet module has not been added withSharedStorageWorklet.addModule()
.
Note:
In the case of WindowSharedStorage
, if the append()
operation doesn't successfully write to the database for a reason other than shared storage not being available, no error is thrown — the operation still fulfills with undefined
.
Examples
window.sharedStorage
.append("integer-list", ",9")
.then(console.log("Value appended to integer list"));
Specifications
Specification |
---|
Shared Storage API # dom-sharedstorage-append |
Browser compatibility
BCD tables only load in the browser