Wf4 beta2: asynchronous Activity

Wf4 beta2 addedAsynccodeactivity,When writing a custom activity,YesBegin/end.When an asynchronous operation is executed, other activities in the workflow are not affected,
However, the workflow is not persistent.

The following is an example:

NamespaceCaryasync

{

Public Sealed Class Filewriter:Asynccodeactivity

{

PublicFilewriter ()

:Base()

{

}

 

Protected Override IasyncresultBeginexecute (AsynccodeactivitycontextContext,AsynccallbackCallback,ObjectState)

{

StringTempfilename =Path. Gettempfilename ();

Console. Writeline ("Writing to file :"+ Tempfilename );

FilestreamFile =File. Open (tempfilename,Filemode. Create );

Context. userstate = file;

Byte[] Bytes =Unicodeencoding. Unicode. getbytes ("123456789");

ReturnFile. beginwrite (bytes,0, Bytes. length, callback, State );

}

 

Protected Override VoidEndexecute (AsynccodeactivitycontextContext,IasyncresultResult)

{

FilestreamFile = (Filestream) Context. userstate;

Try

{

File. endwrite (result );

File. Flush ();

}

Finally

{

File. Close ();

}

}

}

}