SQLite.Net-PCL连接未找到DB [英] SQLite.Net-PCL Connection not finding the DB

问题描述

我一直在尝试创建一个windows手机，我想使用SQLite来存储我的数据，并学习如何使用它在Windows Phone应用程序。为此目的，我使用SQLite.Net-PCL，但我不断得到一个文件未找到异常。我写的代码：

I've been trying to create a windows phone and I'd like to use SQLite to both store my data and learn how to use it on windows phone apps. For this purpose I'm using "SQLite.Net-PCL", but I keep getting a file not found exception. This the code I've written:

        String ConnectionString = Path.Combine(ApplicationData.Current.LocalFolder.Path, Connection);
        if (File.Exists(ConnectionString))
        {
            SQLite.Net.Platform.WindowsPhone8.SQLitePlatformWP8 e = new SQLite.Net.Platform.WindowsPhone8.SQLitePlatformWP8();
            Con = new SQLiteConnection(e,ConnectionString);
        }

        else {
            SQLite.Net.Platform.WindowsPhone8.SQLitePlatformWP8 e = new SQLite.Net.Platform.WindowsPhone8.SQLitePlatformWP8();
            File.Create(ConnectionString);
            Con = new SQLiteConnection(e, ConnectionString);               
        }

我想也许我得到这个错误，因为我手动创建一个空文件，这是问题，如果手机中没有数据库，如何创建一个数据库？

I thought maybe I get this error because I manually create an empty file but if that is the problem, how can I create a DB in case no database exists in the phone ?

推荐答案

public SQLiteConnection(ISQLitePlatform sqlitePlatform, string databasePath, bool storeDateTimeAsTicks = false, IBlobSerializer serializer = null)
    : this(
        sqlitePlatform, databasePath, SQLiteOpenFlags.ReadWrite | SQLiteOpenFlags.Create, storeDateTimeAsTicks, serializer)
{
}

所以你应该打开连接，创建表，应该是这样。

So you should just open the connection, create the tables and that should be that.

class ExampleDataContext
{
    public const string DATABASE_NAME = "data.sqlite";
    private SQLiteConnection connection;

    public TableQuery<Foo> FooTable { get; private set; }
    public TableQuery<Bar> BarTable { get; private set; }

    public ExampleDataContext()
    {
        connection = new SQLiteConnection(new SQLitePlatformWinRT(), Path.Combine(Windows.Storage.ApplicationData.Current.LocalFolder.Path, DATABASE_NAME));

        Initialize();

        FooTable      = connection.Table<Foo>();
        BarTable       = connection.Table<Bar>();
    }

    private void Initialize()
    {
        connection.CreateTable<Foo>();
        connection.CreateTable<Bar>();
    }
}

不要担心初始化，表格只有在还没有时创建。

Don't worry about that Initialize, the tables only get created when they're not there yet.

这篇关于SQLite.Net-PCL连接未找到DB的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！