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IDBRequest

Namespace: SpawnDev.SpawnJS.JSObjects
Inherits: IDBRequest
Source: JSObjects/IDBRequest.cs
MDN Reference: IDBRequest on MDN

The IDBRequest interface of the IndexedDB API provides access to results of asynchronous requests to databases and database objects using event handler attributes. Each reading and writing operation on a database is done using a request. https://developer.mozilla.org/en-US/docs/Web/API/IDBRequest The type to use for the Result property

Constructors

Signature Description
IDBRequest(SpawnJSObjectReference _ref) Deserialization constructor
IDBRequest(SpawnJSObjectReference _ref) Deserialization constructor

Properties

Property Type Access Description
Result TResult get Returns the result of the request. If the request is not completed, the result is not available and an InvalidStateError exception is thrown.
Error DOMException get Returns a DOMException in the event of an unsuccessful request, indicating what went wrong.
ReadyState string get The state of the request. Every request starts in the pending state. The state changes to done when the request completes successfully or when an error occurs.
Transaction IDBTransaction? get The transaction for the request. This property can be null for certain requests, for example those returned from IDBFactory.open unless an upgrade is needed. (You're just connecting to a database, so there is no transaction to return).

Methods

Method Return Type Description
WaitAsync(bool disposeRequest) Task<TResult> if (ReadyState == "done" AND Error == null) returns Result as TResult if (ReadyState == "done" AND Error != null) throws Exception else On onsuccess returns Result as TResult On onerror throws Exception If true, this IDBRequest will be disposed after when the call completes Task<TResult>
ResultAs() T Returns the result of the request. If the request is not completed, the result is not available and an InvalidStateError exception is thrown.
SourceAs() T An object representing the source of the request, such as an IDBIndex, IDBObjectStore or IDBCursor.

Events

Event Type Description
OnError ActionEvent<Event> Fired when an error caused a request to fail.
OnSuccess ActionEvent<Event> Fired when an IDBRequest succeeds.

Examples

SpawnDev.SpawnJS Mapping Note: The JavaScript examples below show the standard Web API usage. In SpawnDev.SpawnJS, the same API is available with C# conventions:

  • Properties and methods use PascalCase (e.g., readyState becomes ReadyState)
  • Events use ActionEvent with +=/-= (e.g., addEventListener("click", fn) becomes OnClick += handler)
  • Async methods return Task<T> instead of Promise<T>
  • Objects should be disposed with using statements
  • Access via JS.Get<IDBRequest>(...) or constructor new IDBRequest(...)
let db;

// Let us open our database
const DBOpenRequest = window.indexedDB.open("toDoList", 4);

// these two event handlers act on the database being
// opened successfully, or not
DBOpenRequest.onerror = (event) => {
  note.appendChild(document.createElement("li")).textContent =
    "Error loading database.";
};

DBOpenRequest.onsuccess = (event) => {
  note.appendChild(document.createElement("li")).textContent =
    "Database initialized.";

  // store the result of opening the database.
  db = DBOpenRequest.result;
};

See full example on MDN