ToListAsync task sequence extension for C#

TaskExtensions.cs

public static class TaskExtensions
{
    public static async Task<List<TItem>> ToListAsync<TItem>(this IEnumerable<Task<TItem>> items)
    {
        var tasks = items.Select(i => i).ToArray();
        await Task.WhenAll(tasks);
        return tasks.Select(t => t.Result).ToList();
    }
}

/// usage:

var viewManagerAndPositions = await _viewManagers
    .Select(async vm => new { ViewManager = vm, Position = await vm.GetPosition() })
    .ToListAsync();