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TaskFactory.FromAsync<TResult> Method (IAsyncResult, Func<IAsyncResult, TResult>, TaskCreationOptions)

Microsoft Silverlight will reach end of support after October 2021. Learn more.

Creates a Task<TResult> that executes an end method function when a specified IAsyncResult completes.

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

Syntax

'Declaration
Public Function FromAsync(Of TResult) ( _
    asyncResult As IAsyncResult, _
    endMethod As Func(Of IAsyncResult, TResult), _
    creationOptions As TaskCreationOptions _
) As Task(Of TResult)
public Task<TResult> FromAsync<TResult>(
    IAsyncResult asyncResult,
    Func<IAsyncResult, TResult> endMethod,
    TaskCreationOptions creationOptions
)

Type Parameters

  • TResult
    The type of the result available through the Task<TResult>.

Parameters

  • asyncResult
    Type: System.IAsyncResult
    The IAsyncResult whose completion should trigger the processing of the endMethod.
  • endMethod
    Type: System.Func<IAsyncResult, TResult>
    The function delegate that processes the completed asyncResult.

Return Value

Type: System.Threading.Tasks.Task<TResult>
A Task<TResult> that represents the asynchronous operation.

Exceptions

Exception Condition
ArgumentNullException

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

-or-

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

ArgumentOutOfRangeException

The exception that is thrown when the creationOptions argument specifies an invalid TaskCreationOptions value. The exception that is thrown when the creationOptions argument specifies an invalid TaskCreationOptions value. For more information, see the Remarks for FromAsync

Version Information

Silverlight

Supported in: 5

Platforms

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