Multiple Errors Using <Task>[Answered] RSS

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  ShowFreeFlyi...

  Member

  8 Points

  22 Posts

  Multiple Errors Using <Task>

  Mar 07, 2016 06:54 PM|ShowFreeFlying|LINK

  When I execute my code below, I get these two compile errors, what do I do to remove them?

  The type or namespace name 'Task' could not be found (are you missing a directive or an assembly)?
  Missing compiler required memeber 'System.Runtime.CompilerServices.AsyncTaskMethodBuilder.Task'
  The return type of an async method must be void, Task or Task<T>

  And here is my code, what do I need to do to remedy?

  namespace nmsp122332
  {
      public partial class HiByeCULater : System.Web.UI.UserControl
      {
          private DataSet gc = new DataSet();
          private DataSet cfg = new DataSet();
          private DataSet app = new DataSet();
  		private DED dogeatdog = new DED();
  
  		protected void Page_Load(object sender, EventArgs e)
  		{
  			try
  			{
  				CheckPermissions();
  				if (!IsPostBack)
  				{
  					Setup();
  					runfast();
  					hideme();
  					eatslow();
  
  					var t1 = runfast();
  					var t2 = hideme();
  					var t3 = eatslow();
  					ShowAllData();
  				}
  			}
  			catch { }
  		}
  
  		async Task runfast()
  		{
  			gc = dogeatdog.runfast();
  		}
  		async Task hideme()
  		{
  			cfg = dogeatdog.hideme();
  		}
  		async Task eatslow()
  		{
  			app = dogeatdog.eatslow();
  		}
  		ShowAllData()
  		{
  			gv1.DataSource = gc;
  			gv1.DataBind();
  			gv2.DataSource = cfg;
  			gv2.DataBind();
  			gv4.DataSource = app;
  			gv4.DataBind();
  		}
  	}
  }
  
  
  

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  gerrylowry

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  Re: Multiple Errors Using <Task>

  Mar 07, 2016 07:38 PM|gerrylowry|LINK

  @ShowFreeFlyi...     welcome to forums.asp.net

  try qualifying Task or adding a reference:

  async  System.Threading.Tasks.Task runfast()

  "The return type of an async method must be void, Task or Task<T>"

  async Task runfast()            //   <===  promise to return a Task
  {
      gc = dogeatdog.runfast();
      return    ??????????????'   //   <===  you are NOT returning a Task
  }

  B-)  Gerry Lowry, Chief Training Architect, Paradigm Mentors Learning never ends... +1 705-999-9195 wasaga beach, ontario canada TIMTOWTDI =.there is more than one way to do it
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  ShowFreeFlyi...

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  Re: Multiple Errors Using <Task>

  Mar 07, 2016 07:46 PM|ShowFreeFlying|LINK

  gerrylowry

  @ShowFreeFlyi...     welcome to forums.asp.net

  try qualifying Task or adding a reference:

  async  System.Threading.Tasks.Task runfast()

  "The return type of an async method must be void, Task or Task<T>"

  async Task runfast()            //   <===  promise to return a Task
  {
      gc = dogeatdog.runfast();
      return    ??????????????'   //   <===  you are NOT returning a Task
  }

  Hello and thank you for your response.  I fully qualified Task and that seems to have removed those compiler errors.  I added a return type, but I must not be understanding what it is asking for.  In the example above, I want to return the dataset being stored in gc so I used this syntax:

  async Task runfast()
  {
  	gc = dogeatdog.runfast();
  	return gc;
  }

  However, that gives me this compiler error:

  Since 'runfast()' is an async method that returns 'Task', a return keyword must not be followed by an object expression. Did you intend to return 'Task<T>'?

• • Reply
  PawanPal

  Contributor

  2400 Points

  669 Posts

  Re: Multiple Errors Using <Task>

  Mar 07, 2016 08:22 PM|PawanPal|LINK

  Hi,

  If you are returning something from your function then it should have a return type like below example. If your gc object is of type int then int, if it is some custom class then the name of the class or anything. More you can read here: https://msdn.microsoft.com/en-us/library/hh191443.aspx

  async Task<int> runfast()
  {
  	gc = dogeatdog.runfast();
  	return gc;
  }
  
  or
  async Task<YourClass> runfast()
  {
  	gc = dogeatdog.runfast();
  	return gc;
  }

  Mark as answer posts that helped you.
  https://pawanpalblog.wordpress.com
  www.jsengineeringworks.com
• • Reply
  ShowFreeFlyi...

  Member

  8 Points

  22 Posts

  Re: Multiple Errors Using <Task>

  Mar 07, 2016 08:37 PM|ShowFreeFlying|LINK

  Thank you for that link, it helped me :) -- I altered my code to and that remedied one compiler issue, but now a new one presents itself.

  async Task<DataSet> runfast()
  {
  	gc = dogeatdog.runfast();
  	return gc;
  }

  How do I overcome this?

  Missing compiler required member 'System.Runtime.CompilerServices.AsyncTaskMethodBuilder`1.Task'

• • Reply
  PawanPal

  Contributor

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  669 Posts

  Re: Multiple Errors Using <Task>

  Mar 07, 2016 08:41 PM|PawanPal|LINK

  Get reference for using System.Runtime.CompilerServices;

  Mark as answer posts that helped you.
  https://pawanpalblog.wordpress.com
  www.jsengineeringworks.com