伙计们,现在我有一个问题,这真的让我想知道。
我目前正在开发一个 Windows 8 RT 应用程序,该应用程序将数据存储到本地,所以我选择使用 SQLite for WinRT(包括 SQLite.cs SQLiteAsync.cs,SQLite3.dll),用于 WinRT 的 SQLite 存储数据库文件默认在应用程序临时文件夹中
public SQLiteConnection (string databasePath, bool storeDateTimeAsTicks = false): this (databasePath, SQLiteOpenFlags.ReadWrite | SQLiteOpenFlags.Create, storeDateTimeAsTicks)
{
}
/// <summary>
/// Constructs a new SQLiteConnection and opens a SQLite database specified by databasePath.
/// </summary>
/// <param name="databasePath">
/// Specifies the path to the database file.
/// </param>
/// <param name="storeDateTimeAsTicks">
/// Specifies whether to store DateTime properties as ticks (true) or strings (false). You
/// absolutely do want to store them as Ticks in all new projects. The default of false is
/// only here for backwards compatibility. There is a *significant* speed advantage, with no
/// down sides, when setting storeDateTimeAsTicks = true.
/// </param>
public SQLiteConnection (string databasePath, SQLiteOpenFlags openFlags, bool storeDateTimeAsTicks = false)
{
DatabasePath = databasePath;
#if NETFX_CORE
SQLite3.SetDirectory(/*temp directory type*/2, Windows.Storage.ApplicationData.Current.TemporaryFolder.Path);
#endif
Sqlite3DatabaseHandle handle;
#if SILVERLIGHT || USE_CSHARP_SQLITE
var r = SQLite3.Open (databasePath, out handle, (int)openFlags, IntPtr.Zero);
#else
// open using the byte[]
// in the case where the path may include Unicode
// force open to using UTF-8 using sqlite3_open_v2
var databasePathAsBytes = GetNullTerminatedUtf8 (DatabasePath);
var r = SQLite3.Open (databasePathAsBytes, out handle, (int) openFlags, IntPtr.Zero);
#endif
Handle = handle;
if (r != SQLite3.Result.OK) {
throw SQLiteException.New (r, String.Format ("Could not open database file: {0} ({1})", DatabasePath, r));
}
_open = true;
StoreDateTimeAsTicks = storeDateTimeAsTicks;
BusyTimeout = TimeSpan.FromSeconds (0.1);
}
分配给应用程序临时文件夹路径。
现在我想将数据库文件保存到另一个文件夹,如文档文件夹,以保存用户数据和行为,当用户重新安装应用程序时导入数据。所以我更改了保存文件夹,代码如下
StorageFolder sourceFolder = await KnownFolders.DocumentsLibrary.GetFolderAsync(FolderName);
DatabasePath = Path.Combine(sourceFolder.Path, DBName);
SQLite3.SetDirectory(/*temp directory type*/2, storeFloderPath);
但它会在以下位置引发异常:
var r = SQLite3.Open(databasePathAsBytes, out handle, (int)openFlags, IntPtr.Zero);
Handle = handle;
if (r != SQLite3.Result.OK)
{
throw SQLiteException.New(r, String.Format("Could not open database file: {0} ({1})", DatabasePath, r));
}
它说无法打开文件。我认为问题可能是'SQLite3.SetDirectory(/ temp directory type /2,storeFloderPath)','2'是stand temp directory type。这些没有官方文档,所以我尝试了从0到6的参数,它不起作用,异常与原始相同。
任何人都知道该怎么做,或者我的代码中有一些错误。提前致谢。