JSReference class
A strong or weak reference to a JS value.
public class JSReference : IDisposablePublic Members
| name | description |
|---|---|
| JSReference(…) | Creates a new instance of a JSReference that holds a strong or weak reference to a JS value. (2 constructors) |
| Handle { get; } | Gets the value handle, or throws an exception if access from the current thread is invalid. |
| IsDisposed { get; } | Gets a value indicating whether the reference has been disposed. |
| IsWeak { get; } | |
| SynchronizationContext { get; } | Gets the synchronization context that must be used to access the referenced value. |
| Dispose() | Releases the reference. |
| GetValue() | Gets the referenced JS value. |
| MakeStrong() | Changes a weak reference into a strong reference, if it is not already strong and the value is still available. |
| MakeWeak() | Changes a strong reference into a weak reference, if it is not already weak. |
| Run(…) | Runs an action with the referenced value, using the JSSynchronizationContext associated with the reference to switch to the JS thread (if necessary) while operating on the value. |
| Run<T>(…) | Runs an action with the referenced value, using the JSSynchronizationContext associated with the reference to switch to the JS thread (if necessary) while operating on the value. |
| TryGetValue(…) | Attempts to get the referenced JS value. |
| static TryCreateReference(…) | Creates a reference to a JS value, if the value is an object, function, or symbol. |
| explicit operator |
Protected Members
| name | description |
|---|---|
| virtual Dispose(…) | |
| override Finalize() |
Remarks
JSValue and related JS handle structs are not valid after their JSValueScope closes -- typically that is when a callback returns. Use a JSReference to maintain a reference to a JS value beyond a single scope.
A JSReference should be disposed when no longer needed; this allows the JS value to be collected by the JS GC if it has no other references. The JSReference class also has a finalizer so that the reference will be released when the C# object is GC'd. However explicit disposal is still preferable when possible.
A "strong" reference ensures the JS value is available at least until the reference is disposed. A "weak" reference does not prevent the JS value from being released collected by the JS garbage-collector, but allows the value to be optimistically retrieved until then.