Question

我正在寻找在我的Win Phone WRT 8.1应用程序中创建一个SQLite数据库;我已经阅读了这篇文章Create a SQLite Database in Windows Phone 8.1 Class Library，我试着写这个课：

    using SQLite;
using System;
using System.Threading.Tasks;
using Windows.Storage;

namespace Functional_Timer
{
    class DatabaseHelper
    {

        private String DB_NAME = "DATABASENAME.db";

        public SQLiteAsyncConnection Conn { get; set; }

        public DatabaseHelper()
        {
            Conn = new SQLiteAsyncConnection(DB_NAME);
            this.InitDb();

        }

        public async void InitDb()
        {
            // Create Db if not exist
            bool dbExist = await CheckDbAsync();
            if (!dbExist)
            {
                await CreateDatabaseAsync();
            }
        }

        public async Task<bool> CheckDbAsync()
        {
            bool dbExist = true;

            try
            {
                //ERRORE!!!
                StorageFile sf = await ApplicationData.Current.LocalFolder.GetFileAsync(DB_NAME);
            }
            catch (Exception)
            {
                dbExist = false;
            }

            return dbExist;
        }

        private async Task CreateDatabaseAsync()
        {
            //add tables here
            //example: await Conn.CreateTableAsync<DbComment>();
        }

    }
}

我已经在我的应用程序主页中按照以下说明调用了这个类：

this.InitializeComponent();
        commentDataSource = new CommentDataSource(db);

但是，如果我运行它，我会看到，在评论“ERRORE !!!”的行中第一个，以下消息：

Exception thrown: 'System.IO.FileNotFoundException' in mscorlib.ni.dll
Ulteriori informazioni: The system cannot find the file specified. (Exception from HRESULT: 0x80070002)

为什么呢？你能帮助理解和解决它吗？非常感谢所有人。

编辑：在控制台中，我看到了消息

l'SDK“SQLite.WP81，Version = 3.8.10.2”dipende dai seguenti SDK“Microsoft.VCLibs，version = 12.0”che non sono stati aggiunti al progetto o non sono stati trovati。 Assicurarsi di aggiungere queste dipendenze al progettooèpossibileche si verifichino problemi di runtime。 Èpossibileaggiungere dipendenze al progetto mediante Gestione riferimenti。

但是，如果我尝试在程序包管理器控制台中添加以下命令“Install-Package Microsoft.VCLibs.120.SDKReference -PRE”，我会看到此错误：

Install-Package : Unable to find package 'Microsoft.VCLibs.120.SDKReference'

At line:1 char:1

+ Install-Package Microsoft.VCLibs.120.SDKReference -Pre

+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

    + CategoryInfo          : NotSpecified: (:) [Install-Package], Exception

    + FullyQualifiedErrorId : NuGetCmdletUnhandledException,NuGet.PackageManagement.PowerShellCmdlets.InstallPackageCommand

Windows Phone 8.1 WRT＆amp; SQLite，创建数据库

0 个答案: