我的连接字符串在自己生成的连接字符串上出错。我将如何解决这个问题？

Question

第一次在 Visual Studios 2017 中使用 DB/SQL 所以我创建了我自己的数据库，里面有一个表 现在我希望我的代码连接到数据库并使用生成的 connectionString 但现在我收到类似的错误：System.Data.SqlClient.SqlException

我的连接 OPEN 出了点问题

namespace WindowsFormsApp2
{
    class DBConnect
    {
        public void connectDB()
        { 
            SqlConnection con = new SqlConnection(@"Data Source=(LocalDB)\MSSQLLocalDB; AttachDbFilename = C:\Users\xflak\OneDrive\Documenten\GitHub\ItemDatabase - UI\WindowsFormsApp2\Database1.mdf; Integrated Security = True");
            try
            {
                con.Open();
                Console.WriteLine("Connection Open!");
            }catch(Exception ex)
            {
                Console.WriteLine(ex.StackTrace);
            }
        }
    }
}

旧堆栈跟踪

Exception thrown: 'System.Data.SqlClient.SqlException' in System.Data.dll
   bij System.Data.SqlClient.SqlInternalConnectionTds..ctor(DbConnectionPoolIdentity identity, SqlConnectionString connectionOptions, SqlCredential credential, Object providerInfo, String newPassword, SecureString newSecurePassword, Boolean redirectedUserInstance, SqlConnectionString userConnectionOptions, SessionData reconnectSessionData, DbConnectionPool pool, String accessToken, Boolean applyTransientFaultHandling)
   bij System.Data.SqlClient.SqlConnectionFactory.CreateConnection(DbConnectionOptions options, DbConnectionPoolKey poolKey, Object poolGroupProviderInfo, DbConnectionPool pool, DbConnection owningConnection, DbConnectionOptions userOptions)
   bij System.Data.ProviderBase.DbConnectionFactory.CreatePooledConnection(DbConnectionPool pool, DbConnection owningObject, DbConnectionOptions options, DbConnectionPoolKey poolKey, DbConnectionOptions userOptions)
   bij System.Data.ProviderBase.DbConnectionPool.CreateObject(DbConnection owningObject, DbConnectionOptions userOptions, DbConnectionInternal oldConnection)
   bij System.Data.ProviderBase.DbConnectionPool.UserCreateRequest(DbConnection owningObject, DbConnectionOptions userOptions, DbConnectionInternal oldConnection)
   bij System.Data.ProviderBase.DbConnectionPool.TryGetConnection(DbConnection owningObject, UInt32 waitForMultipleObjectsTimeout, Boolean allowCreate, Boolean onlyOneCheckConnection, DbConnectionOptions userOptions, DbConnectionInternal& connection)
   bij System.Data.ProviderBase.DbConnectionPool.TryGetConnection(DbConnection owningObject, TaskCompletionSource`1 retry, DbConnectionOptions userOptions, DbConnectionInternal& connection)
   bij System.Data.ProviderBase.DbConnectionFactory.TryGetConnection(DbConnection owningConnection, TaskCompletionSource`1 retry, DbConnectionOptions userOptions, DbConnectionInternal oldConnection, DbConnectionInternal& connection)
   bij System.Data.ProviderBase.DbConnectionInternal.TryOpenConnectionInternal(DbConnection outerConnection, DbConnectionFactory connectionFactory, TaskCompletionSource`1 retry, DbConnectionOptions userOptions)
   bij System.Data.ProviderBase.DbConnectionClosed.TryOpenConnection(DbConnection outerConnection, DbConnectionFactory connectionFactory, TaskCompletionSource`1 retry, DbConnectionOptions userOptions)
   bij System.Data.SqlClient.SqlConnection.TryOpenInner(TaskCompletionSource`1 retry)
   bij System.Data.SqlClient.SqlConnection.TryOpen(TaskCompletionSource`1 retry)
   bij System.Data.SqlClient.SqlConnection.Open()
   bij WindowsFormsApp2.DBConnect.connectDB() in C:\Users\xflak\OneDrive\Documenten\GitHub\ItemDatabase-UI\WindowsFormsApp2\DBConnect.cs:regel 17

带有 SqlException 的新 Stacktrace en ex.ToString();

Exception thrown: 'System.Data.SqlClient.SqlException' in System.Data.dll
System.Data.SqlClient.SqlException (0x80131904): An attempt to attach an auto-named database for file C:\Users\xflak\OneDrive\Documenten\GitHub\ItemDatabase - UI\WindowsFormsApp2\Database1.mdf failed. A database with the same name exists, or specified file cannot be opened, or it is located on UNC share.
   bij System.Data.SqlClient.SqlInternalConnectionTds..ctor(DbConnectionPoolIdentity identity, SqlConnectionString connectionOptions, SqlCredential credential, Object providerInfo, String newPassword, SecureString newSecurePassword, Boolean redirectedUserInstance, SqlConnectionString userConnectionOptions, SessionData reconnectSessionData, DbConnectionPool pool, String accessToken, Boolean applyTransientFaultHandling)
   bij System.Data.SqlClient.SqlConnectionFactory.CreateConnection(DbConnectionOptions options, DbConnectionPoolKey poolKey, Object poolGroupProviderInfo, DbConnectionPool pool, DbConnection owningConnection, DbConnectionOptions userOptions)
   bij System.Data.ProviderBase.DbConnectionFactory.CreatePooledConnection(DbConnectionPool pool, DbConnection owningObject, DbConnectionOptions options, DbConnectionPoolKey poolKey, DbConnectionOptions userOptions)
   bij System.Data.ProviderBase.DbConnectionPool.CreateObject(DbConnection owningObject, DbConnectionOptions userOptions, DbConnectionInternal oldConnection)
   bij System.Data.ProviderBase.DbConnectionPool.UserCreateRequest(DbConnection owningObject, DbConnectionOptions userOptions, DbConnectionInternal oldConnection)
   bij System.Data.ProviderBase.DbConnectionPool.TryGetConnection(DbConnection owningObject, UInt32 waitForMultipleObjectsTimeout, Boolean allowCreate, Boolean onlyOneCheckConnection, DbConnectionOptions userOptions, DbConnectionInternal& connection)
   bij System.Data.ProviderBase.DbConnectionPool.TryGetConnection(DbConnection owningObject, TaskCompletionSource`1 retry, DbConnectionOptions userOptions, DbConnectionInternal& connection)
   bij System.Data.ProviderBase.DbConnectionFactory.TryGetConnection(DbConnection owningConnection, TaskCompletionSource`1 retry, DbConnectionOptions userOptions, DbConnectionInternal oldConnection, DbConnectionInternal& connection)
   bij System.Data.ProviderBase.DbConnectionInternal.TryOpenConnectionInternal(DbConnection outerConnection, DbConnectionFactory connectionFactory, TaskCompletionSource`1 retry, DbConnectionOptions userOptions)
   bij System.Data.ProviderBase.DbConnectionClosed.TryOpenConnection(DbConnection outerConnection, DbConnectionFactory connectionFactory, TaskCompletionSource`1 retry, DbConnectionOptions userOptions)
   bij System.Data.SqlClient.SqlConnection.TryOpenInner(TaskCompletionSource`1 retry)
   bij System.Data.SqlClient.SqlConnection.TryOpen(TaskCompletionSource`1 retry)
   bij System.Data.SqlClient.SqlConnection.Open()
   bij WindowsFormsApp2.DBConnect.connectDB() in C:\Users\xflak\OneDrive\Documenten\GitHub\ItemDatabase-UI\WindowsFormsApp2\DBConnect.cs:regel 17
ClientConnectionId:200efe66-c5b0-4085-acb2-67a1c554ed67
Error Number:15350,State:1,Class:14

相关部分是：

SqlException (0x80131904)：尝试为文件 C:\Users\xflak\OneDrive\Documenten\GitHub\ItemDatabase - UI\WindowsFormsApp2\Database1.mdf 附加自动命名数据库失败。存在同名数据库，或指定文件无法打开，或位于 UNC 共享上。

Answer 1

尝试不使用 AttachDbFilename 并作为初始目录输入您的数据库名称。

SqlConnection con = new SqlConnection(@"Data Source=(LocalDB)\MSSQLLocalDB; Initial Catalog=Your database name ; Integrated Security = True")

Answer 2

我猜，您需要将 .mdf 文件放在 D:/ 或 E:/ 等可访问驱动器中，并尝试将其放在没有空格的文件夹中。

我看到您的路径中有多个空格。 ('ItemDatabase - UI')