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SharedStorage: append() method - Web APIs | MDN
SharedStorage: append() method Limited availability
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.
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.
A Promise
that fulfills with undefined
.
The Promise
rejects with a TypeError
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/or value
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
, the Promise
rejects with a TypeError
if the worklet module has not been added with SharedStorageWorklet.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
.
window.sharedStorage
.append("integer-list", ",9")
.then(console.log("Value appended to integer list"));