Question

我必须安装一个干净的系统，然后我丢失了一个正在制作的项目。然后我从头开始，但连接有困难。我收到错误＆＃34;不是有效的文件名。＆＃34;奇怪的是我能够检索组合框的数据。以下是例外情况：

Interception de System.Data.OleDb.OleDbException
  ErrorCode=-2147467259
  HResult=-2147467259
  Message=Not a valid file name.
  Source=Microsoft Office Access Database Engine
  StackTrace:
       à System.Data.OleDb.OleDbConnectionInternal..ctor(OleDbConnectionString constr, OleDbConnection connection)
       à System.Data.OleDb.OleDbConnectionFactory.CreateConnection(DbConnectionOptions options, DbConnectionPoolKey poolKey, Object poolGroupProviderInfo, DbConnectionPool pool, DbConnection owningObject)
       à System.Data.ProviderBase.DbConnectionFactory.CreateConnection(DbConnectionOptions options, DbConnectionPoolKey poolKey, Object poolGroupProviderInfo, DbConnectionPool pool, DbConnection owningConnection, DbConnectionOptions userOptions)
       à System.Data.ProviderBase.DbConnectionFactory.CreateNonPooledConnection(DbConnection owningConnection, DbConnectionPoolGroup poolGroup, DbConnectionOptions userOptions)
       à System.Data.ProviderBase.DbConnectionFactory.TryGetConnection(DbConnection owningConnection, TaskCompletionSource`1 retry, DbConnectionOptions userOptions, DbConnectionInternal oldConnection, DbConnectionInternal& connection)
       à System.Data.ProviderBase.DbConnectionInternal.TryOpenConnectionInternal(DbConnection outerConnection, DbConnectionFactory connectionFactory, TaskCompletionSource`1 retry, DbConnectionOptions userOptions)
       à System.Data.ProviderBase.DbConnectionClosed.TryOpenConnection(DbConnection outerConnection, DbConnectionFactory connectionFactory, TaskCompletionSource`1 retry, DbConnectionOptions userOptions)
       à System.Data.ProviderBase.DbConnectionInternal.OpenConnection(DbConnection outerConnection, DbConnectionFactory connectionFactory)
       à System.Data.OleDb.OleDbConnection.Open()
       à GestBanque.Securite.rechutil() dans F:\CODEBASE\HLVL\DotNet\GestBanque\GestBanque\Securite.vb:ligne 39
  InnerException:

这是错误的代码：

Private Sub rechutil()
        Try
            Dim dr As OleDbDataReader
            Dim cmdselect As New OleDbCommand
            Dim sql As String
            Dim cn As String
            Dim sconnexion As OleDbConnection
            cn = "provider=Microsoft.ACE.OLEDB.12.0;Password=;User ID=Admin;Data Source=‪F:\GPI3\GestBanque.accdb"
            sconnexion = New OleDbConnection(cn)
            sconnexion.Open() ' The error is raised here
            cmdselect.Connection = sconnexion
            cmdselect.CommandType = CommandType.Text
            sql = "SELECT nom, motdepasse FROM UTILISATEUR WHERE nom=? AND motdepasse=?"
            cmdselect.CommandText = sql
            cmdselect.Parameters.Add("no", OleDbType.Char)
            cmdselect.Parameters.Add("mo", OleDbType.Char)
            cmdselect.Parameters("no").Value = cmbnom.Text
            cmdselect.Parameters("mo").Value = txtpass.Text
            dr = cmdselect.ExecuteReader
            If dr.HasRows Then
                Accueil.Show()
            Else
                MessageBox.Show("Désolé, Accès refusé, Mot de passe erronné", "Authentification", MessageBoxButtons.OK, MessageBoxIcon.Error)
                cmbnom.Text = ""
                txtpass.Text = ""
            End If
            sconnexion.Close()
        Catch ex As Exception
            MessageBox.Show(ex.Message, "Authentification", MessageBoxButtons.OK, MessageBoxIcon.Error)
        End Try
    End Sub

相反，这个程序非常有效：

Private Sub loadcombo()
        Try
            Dim dr As OleDbDataReader
            Dim cmdselect As New OleDbCommand
            Dim sql As String
            Dim cn As String
            Dim sconnexion As OleDbConnection
            cn = "provider=Microsoft.ACE.OLEDB.12.0;Password=;User ID=Admin;Data Source=F:\GPI3\GestBanque.accdb"
            sconnexion = New OleDbConnection(cn)
            sconnexion.Open()
            cmdselect.Connection = sconnexion
            cmdselect.CommandType = CommandType.Text
            sql = "SELECT nom FROM UTILISATEUR ORDER BY nom"
            cmdselect.CommandText = sql
            dr = cmdselect.ExecuteReader
            cmbnom.Items.Clear()
            While dr.Read
                cmbnom.Items.Add(dr.GetValue(0))
            End While
            sconnexion.Close()
        Catch ex As Exception
            MessageBox.Show(ex.Message, "Chargement des noms", MessageBoxButtons.OK, MessageBoxIcon.Error)
        End Try
    End Sub.

以下是截屏：Screen capt

我已经搜索了大约一个月但在各种论坛上都找不到解决方案。提前谢谢。

Answer 1

当遇到像这样的奇怪错误时，请检查您的字符串是否包含可能通过复制和粘贴引入的不可见的Unicode字符。例如，这行VB.NET代码看起来非常温和：

Dim spec As String = "‪‪W:\test.accdb"

但如果我运行代码

Dim spec As String = "‪‪W:\test.accdb"
For i As Integer = 0 To 4
    Console.WriteLine(Hex(AscW(spec.Substring(i, 1))))
Next

我在控制台输出中看到了这个

202A
202A
57
3A
5C

它告诉我字符串的前两个字符是不可见 Unicode“从左到右嵌入”字符U+202A。尽管字符串看起来像一个有效的路径规范，但实际上并非如此。

确认

通过下载项目确认。 “Securite.vb”的第37行包含紧接在“F：”之前引用的上面不可见的Unicode字符（U + 202A），但第12行不包含该字符。这就是为什么一个Sub失败而另一个没有失败的原因。

通过VB.NET 2010连接到Access 2013数据库时，不是有效的文件名错误

1 个答案:

确认