TaskFactory.FromAsync Method (Func<AsyncCallback, Object, IAsyncResult>, Action<IAsyncResult>, Object, TaskCreationOptions)

Creates a Task that represents a pair of begin and end methods that conform to the Asynchronous Programming Model pattern.

Namespace:  System.Threading.Tasks
Assembly:  mscorlib (in mscorlib.dll)


Public Function FromAsync ( _
    beginMethod As Func(Of AsyncCallback, Object, IAsyncResult), _
    endMethod As Action(Of IAsyncResult), _
    state As Object, _
    creationOptions As TaskCreationOptions _
) As Task
public Task FromAsync(
    Func<AsyncCallback, Object, IAsyncResult> beginMethod,
    Action<IAsyncResult> endMethod,
    Object state,
    TaskCreationOptions creationOptions


  • state
    Type: System.Object
    An object containing data to be used by the beginMethod delegate.

Return Value

Type: System.Threading.Tasks.Task
The created Task that represents the asynchronous operation.


Exception Condition

The exception that is thrown when the beginMethod argument is null.


The exception that is thrown when the endMethod argument is null.


The exception that is thrown when the creationOptions argument specifies an invalid TaskCreationOptions value.


This method throws any exceptions thrown by the beginMethod. The TaskCreationOptions values PreferFairness, LongRunning and AttachedToParent are all mutually exclusive. In the FromAsync methods, either LongRunning or AttachedToParent by themselves will cause an ArgumentOutOfRangeException to be thrown.

Version Information


Supported in: 5


For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.