如何读取config.ini文件中的连接字符串

Question

i have an config.ini file in my project this is the data save in my ini file shown below. config where DESKTOP-UAGO7SB\\SQLEXPRESS is the data source, admin is the uid and xxxx is the pwd i have a following code to read the data in config.ini file in my module

Public Function checkServer() As Boolean
    Try

        With frmSettings
            .OpenFileDialog1.FileName = Application.StartupPath & "\Config.ini"
            openedFileStream = .OpenFileDialog1.OpenFile()
        End With

        ReDim dataBytes(openedFileStream.Length - 1) 'Init 
        openedFileStream.Read(dataBytes, 0, openedFileStream.Length)
        openedFileStream.Close()
        tmpStr = System.Text.Encoding.Unicode.GetString(dataBytes)

        With frmSettings
            If Split(tmpStr, ":")(4) = "1" Then
                'network
                CnString = "Data Source=" & Split(tmpStr, ":")(0) & _
                           ";database=DBMISO" & _
                           ";uid=" & Split(tmpStr, ":")(2) & _
                           ";pwd=" & Split(tmpStr, ":")(3)

            Else
                'local
                'MsgBox(Split(tmpStr, ":")(1))
                CnString = "Data Source=" & Split(tmpStr, ":")(1) & _
                           ";Database=DBMISO; Trusted_Connection=yes;"
            End If
        End With
        Dim sqlCon As New SqlConnection
        sqlCon.ConnectionString = CnString
        sqlCon.Open()
        checkServer = True
        sqlCon.Close()
    Catch ex As Exception
        checkServer = False
    End Try
End Function

whenever i call the CnString to connect the database it gives me an error

The ConnectionString property has not been initialized

Answer 1

A lot of things don't make sense in your code or are plain wrong.
You are working with NET so you should use the Framework classes and methods not the old Visual Basic function maintained just for compatibility

Try
    ' Read all the text from your config file
    Dim configData = File.ReadAllText(Application.StartupPath & "\Config.ini")
    ' Split it once and for all
    Dim configParts = configData.Split(":"c)

    ' You expect your config to have at least 4 parts
    if configParts.Length >= 4 Then

        ' Arrays start at zero so the 1 is at index 3 not 4
        If configParts(3) = "1" Then

            ' Again, arrays start at index zero.....
            CnString = "Data Source=" & configParts(0) & _
                       ";database=DBMISO" & _
                       ";uid=" & configParts(1) & _
                       ";pwd=" & configParts(2)
        Else
            'local
            CnString = "Data Source=" & configParts(0) & _
                       ";Database=DBMISO; Trusted_Connection=yes;"
        End If

        ' Enclose in a using statement to dispose the connection also in case
        ' of exceptions
        Using sqlCon = New SqlConnection(CnString)
            sqlCon.Open()
            checkServer = True
        End Using
    Else
        MessageBox.Show("Incorrect config.ini")
    End If
Catch ex As Exception
    MessageBox.Show(ex.Message)
End Try
return checkServer

After all this effort perhaps you should consider that NET has a proven infrastructure to deal with connectionstrings and with configuration files. You should really stop using this approach and learn how to use a configuration file and how to handle a connection string from a config file

Answer 2

Assuming that you have a string named "YourConnectionStringName", this should work:

Dim cnString As String = Web.Configuration.WebConfigurationManager.ConnectionStrings("YourConnectionStringName").ConnectionString

You will need to add a reference to System.Web.