除非与异步代码一起使用，否则WPF绑定不起作用

Question

我有一个Label，其Content属性绑定到ViewModel（Prism / MVVM）上的字符串。当我运行此方法时，将“ pending”分配给该字符串，该值会更改，但是视图永远不会更新。但是，它确实在第二个分配（“成功”）上更新。 我摆弄着试图用RaisePropertyChanged强制进行更新而没有成功，然后尝试运行部分代码异步。那行得通！？！ -但我不知道为什么。关于此问题有任何想法吗？没有异步解决方法的任何补救措施？

XAML：

<Label
     Content="{Binding DbaseCreateSuccess, UpdateSourceTrigger=PropertyChanged}">
</Label>

方法同步：

private void DbaseCreate()
{
    DbaseCreateSuccess = "pending";

    string[] files = Directory.GetFiles("Scripts", "*.*", SearchOption.AllDirectories);

    String databaseName = "testbase";
    String databaseScript = "testbase.sql";
    int fileCount = 0;

        foreach (String file in files)
        {
            if (file.Contains(databaseScript))
            {
                DataService.Runscript(file);
            }
        }

        foreach (String file in files)
        {
            FileInfo info = new FileInfo(file);
            Trace.WriteLine("FileExtension: " + info.Extension);

            if (info.Extension == ".sql" && !file.Contains(databaseScript))
            {
                ++fileCount;
                DataService.Runscript(file, databaseName);
            }
        }

    if (DataService.GetTableNames(databaseName).Count == fileCount)
    {
        DbaseCreateSuccess = "success";
    }

方法异步：

private async void DbaseCreate()
{
    DbaseCreateSuccess = "pending";

    string[] files = Directory.GetFiles("Scripts", "*.*", SearchOption.AllDirectories);

    String databaseName = "testbase";
    String databaseScript = "testbase.sql";
    int fileCount = 0;

    await Task.Factory.StartNew(() =>
    {
        foreach (String file in files)
        {
            if (file.Contains(databaseScript))
            {
                DataService.Runscript(file);
            }
        }

        foreach (String file in files)
        {
            FileInfo info = new FileInfo(file);
            Trace.WriteLine("FileExtension: " + info.Extension);

            if (info.Extension == ".sql" && !file.Contains(databaseScript))
            {
                ++fileCount;
                DataService.Runscript(file, databaseName);
            }
        }
    });

    if (DataService.GetTableNames(databaseName).Count == fileCount)
    {
        DbaseCreateSuccess = "success";
    }
}

ViewModel：

 public class DatabaseAdminViewModel : BindableBase
 {

    private readonly IUnityContainer _container;
    private readonly IRegionManager _regionManager;

    private String _DbaseCreateSuccess;
    public String DbaseCreateSuccess { get { return _DbaseCreateSuccess; } set { SetProperty(ref _DbaseCreateSuccess, value, "DbaseCreateSuccess"); } }

    public DelegateCommand DbaseCreateCommand { get; set; }


    public DatabaseAdminViewModel(IUnityContainer container, IRegionManager regionManager)
    {
        _regionManager = regionManager;
        _container = container;

        DbaseCreateSuccess = "idle";

        DbaseCreateCommand = new DelegateCommand(DbaseCreate);

    }

    private async void DbaseCreate()
    {
        DbaseCreateSuccess = "pending";

        string[] files = Directory.GetFiles("Scripts", "*.*", SearchOption.AllDirectories);

        String databaseName = "testbase";
        String databaseScript = "testbase.sql";
        int fileCount = 0;

        await Task.Factory.StartNew(() =>
        {
            foreach (String file in files)
            {
                if (file.Contains(databaseScript))
                {
                    DataService.Runscript(file);
                }
            }

            foreach (String file in files)
            {
                FileInfo info = new FileInfo(file);
                Trace.WriteLine("FileExtension: " + info.Extension);

                if (info.Extension == ".sql" && !file.Contains(databaseScript))
                {
                    ++fileCount;
                    DataService.Runscript(file, databaseName);
                }
            }
        });

        if (DataService.GetTableNames(databaseName).Count == fileCount)
        {
            DbaseCreateSuccess = "success";
        }
    }
}