無法使用連接字符串連接到服務器

Question

所以這是我的代碼：

Private adoConnection As System.Data.SqlClient.SqlConnection
Private adoadapterFillDSUsers As New System.Data.SqlClient.SqlDataAdapter()
Private ServerName As String = ""
Private ConnectionString As String = ""

 Private Sub adoconn()
        adoConnection = New System.Data.SqlClient.SqlConnection()
        adoConnection.ConnectionString = DataManager.DataManager.ConnectionString
    End Sub
    Public Sub ContinueInit()
        ReadRegistry()
        Dim currRegKey As RegistryKey
        Dim newRegKey As RegistryKey
        currRegKey = Registry.CurrentConfig
        Try
            newRegKey = currRegKey.OpenSubKey("Hoh_Dev\Data")
        Catch ex As Exception
            Return
        End Try
        Try
            MREZA = newRegKey.GetValue("Mreza")
            ServerName = newRegKey.GetValue("ServerName")
        Catch ex As Exception
            Return
        End Try

        If MREZA = "D" Then
            ConnectionString = "Data Source=" & ServerName & ";Integrated Security = SSPI;"
        Else
            If MREZA = "W" Then
                ConnectionString = "Data Source=" & ServerName & ";Database=" & DataBaseName & ";user id=xxx;pwd=xxx;"
            End If
        End If
        adoconn()
    End Sub

自從我每次想連接到服務器並使用它時，我就已經失去了理智：

If adoConnection.State = ConnectionState.Closed Then adoConnection.Open()
Try
  DataManager.DataManager.adoCommand.ExecuteNonQuery()
Catch OpenConnectionError As System.Data.SqlClient.SqlException
End Try

我收到此錯誤：

The ConnectionString property has not been initialized.

我從表單加載事件中調用ContinueInit子：

 Private Sub LogIn_Load(sender As Object, e As EventArgs) Handles MyBase.Load
        ContinueInit()

        Me.TextBox1.Focus()
        Me.TransparencyKey = BackColor
        Me.Button2.Visible = False
        Me.Button1.Visible = False
        TextBox2.PasswordChar = "*"
    End Sub

代碼在adoConnection.Open()處破裂，這意味着我什至無法打開與服務器的連接，所以可以執行SQL查詢，這只會導致我沒有設置好東西。

Answer 1

您的連接對象未填寫ConnectionString 。

不知道什么是DataManager.DataManager，但我猜測您正在通過在DataManager類中創建DataManager類的共享實例來做某事，並且您將其稱為DataManager。 （非常令人困惑）但是，我想您需要對此進行研究，並逐步閱讀代碼以查找為什么連接字符串為空字符串。