Async property in c#

Question

In my windows 8 application there is a global class where there are a few static properties like:

public class EnvironmentEx
{
     public static Us         


        

Answer 1

Good solution: Don't make a property. Make an async method.

"I hate await, how can I make everything synchronous?" solution: How to call asynchronous method from synchronous method in C#?

Answer 2

use the await keyword

 public async static StorageFolder GetAppRootFolder() 
 { 
          return await ApplicationData
                      .LocalFolder
                      .CreateFolderAsync("folderName");
 } 

and in your code

var myRootFolder = await StaticClass.GetAppRootFolder(); // this is a synchronous call as we are calling await immediately and will return the StorageFolder.

Answer 3

Here is an idea.

public Task<int> Prop {
    get
    {
        Func<Task<int>> f = async () => 
        { 
            await Task.Delay(1000); return 0; 
        };
        return f();
    }
}

private async void Test() 
{
    await this.Prop;
}

but it creates a new Func object for every call this would do the same

public Task<int> Prop {
    get
    {
        return Task.Delay(1000).ContinueWith((task)=>0);
    }
}

You can't await a set since await a.Prop = 1; is not allowed

Answer 4

I suggest you use asynchronous lazy initialization.

public static readonly AsyncLazy<StorageFolder> AppRootFolder =
    new AsyncLazy<StorageFolder>(() =>
    {
      return KnownFolders.DocumentsLibrary                    
          .CreateFolderAsync("theApp", CreationCollisionOption.OpenIfExists)
          .AsTask();
    });

You can then await it directly:

var rootFolder = await EnvironmentEx.AppRootFolder;