C# 以编程方式连接到 SQL 服务器 CE

Question

我对数据库编程完全陌生。我正在使用 Visual Studio 2010 并希望以编程方式创建数据库。

到目前为止，我已经尝试像这样连接到 SQL Server Compact Edition：

public class HistoryDBAccess
{
    private SqlConnection conn = new SqlConnection();

    public HistoryDBAccess()
    {
        conn.ConnectionString = @"Server=localhost;Integrated security=SSPI;database=master";
        string str = "CREATE DATABASE MyDatabase ON PRIMARY " +
            "(NAME = MyDatabase_Data, " +
            "FILENAME = 'C:\\MyDatabaseData.mdf', " +
            "SIZE = 2MB, MAXSIZE = 10MB, FILEGROWTH = 10%) " +
            "LOG ON (NAME = MyDatabase_Log, " +
            "FILENAME = 'C:\\MyDatabaseLog.ldf', " +
            "SIZE = 1MB, " +
            "MAXSIZE = 5MB, " +
            "FILEGROWTH = 10%)";

        SqlCommand myCommand = new SqlCommand(str, conn);
        try
        {
            conn.Open();
            myCommand.ExecuteNonQuery();
            MessageBox.Show("DataBase is Created Successfully", "MyProgram", MessageBoxButtons.OK, MessageBoxIcon.Information);
        }
        catch (System.Exception ex)
        {
            MessageBox.Show(ex.ToString(), "MyProgram", MessageBoxButtons.OK, MessageBoxIcon.Information);
        }
        finally
        {
            if (conn.State == System.Data.ConnectionState.Open)
            {
                conn.Close();
            }
        }

    }
}

Ctor 中的连接失败，并显示无法建立连接的消息。

使用VS2010的数据库向导很好，但是如何在windows 7下看到SQLCe服务器呢？

它是否在控制面板下方，我需要在连接字符串中输入默认密码吗？

非常感谢，

于尔根

Answer 1

我认为您应该使用服务器资源管理器（或数据库资源管理器）在您的项目中添加与数据库的连接，然后检查您的连接字符串。

Answer 2

您似乎试图在打开连接之前传递 con 对象。

所以试试这个并告诉我。

 public HistoryDBAccess()
    {
        conn.ConnectionString = @"Server=localhost;Integrated security=SSPI;database=master";
        string str = "CREATE DATABASE MyDatabase ON PRIMARY " +
            "(NAME = MyDatabase_Data, " +
            "FILENAME = 'C:\\MyDatabaseData.mdf', " +
            "SIZE = 2MB, MAXSIZE = 10MB, FILEGROWTH = 10%) " +
            "LOG ON (NAME = MyDatabase_Log, " +
            "FILENAME = 'C:\\MyDatabaseLog.ldf', " +
            "SIZE = 1MB, " +
            "MAXSIZE = 5MB, " +
            "FILEGROWTH = 10%)";
          conn.Open();

        SqlCommand myCommand = new SqlCommand(str, conn);
        try
        {

            myCommand.ExecuteNonQuery();
            MessageBox.Show("DataBase is Created Successfully", "MyProgram", MessageBoxButtons.OK, MessageBoxIcon.Information);
        }
        catch (System.Exception ex)
        {
            MessageBox.Show(ex.ToString(), "MyProgram", MessageBoxButtons.OK, MessageBoxIcon.Information);
        }
        finally
        {
            if (conn.State == System.Data.ConnectionState.Open)
            {
                conn.Close();
            }
        }

    }
}

Answer 3

创建它后，您可能会想要与它进行交互。您应该考虑使用 NHibernate。它有一个名为 SchemaExport 的功能，可以随意删除和创建数据库。

这是一个使用 SQL Express 的示例，但使用 Compact Edition 并没有太大的不同。您可以通过在 Visual Studio 中打开 NHibernate 并单击 Project > Manage NuGet Packages，然后在 All Online 中搜索 NHibernate 来将 NHibernate 安装到您的项目中。

public class NHContext
{
    protected static Configuration NHConfiguration;
    protected static ISessionFactory SessionFactory;

    public static void DropDatabase()
    {
        new SchemaExport(NHConfiguration).Drop(false, true);
    }

    public static void CreateDatabase()
    {
        new SchemaExport(NHConfiguration).Create(false, true);
    }

    protected static Configuration configureNHibernate()
    {
        var configure = new Configuration();
        configure.SessionFactoryName("BuildIt");

        configure.DataBaseIntegration(db =>
        {
            db.Dialect<MsSql2008Dialect>();
            db.Driver<Sql2008ClientDriver>();//db.Driver<SqlClientDriver>();
            db.KeywordsAutoImport = Hbm2DDLKeyWords.AutoQuote;
            db.IsolationLevel = IsolationLevel.ReadCommitted;
            db.ConnectionString = @"Data Source=.\SQLEXPRESS;Persist Security Info=True;Integrated Security=SSPI;Initial Catalog=NHibernate32Test;User Instance=False";
            db.Timeout = 10;

            // For testing
            db.LogFormattedSql = true;
            db.LogSqlInConsole = true;
            db.AutoCommentSql = true;
        });

        return configure;
    }

    public static void Setup()
    {
        NHConfiguration = configureNHibernate();
        HbmMapping mapping = getMappings();
        NHConfiguration.AddDeserializedMapping(mapping, "NHibernate32Test");
        SchemaMetadataUpdater.QuoteTableAndColumns(NHConfiguration);
        SessionFactory = NHConfiguration.BuildSessionFactory();
    }
}