async , await .NET 4.5

you still can use Task.Wait method


 The await operator is applied to a task in an asynchronous method to suspend the execution of the method until the awaited task completes. The task represents ongoing work.

The asynchronous method in which await is used must be modified by the async keyword. Such a method, defined by using the async modifier, and usually containing one or more await expressions, is referred to as an async method.


private async Task SumPageSizesAsync()
{
    // To use the HttpClient type in desktop apps, you must include a using directive and add a
    // reference for the System.Net.Http namespace.
    HttpClient client = new HttpClient();
    // . . .
    Task getContentsTask = client.GetByteArrayAsync(url);
    byte[] urlContents = await getContentsTask;

    // Equivalently, now that you see how it works, you can write the same thing in a single line.
    //byte[] urlContents = await client.GetByteArrayAsync(url);
    // . . .
}