I have a function in VB.NET that authenticates a user towards a MySQL database before launching the main application. Here's the code of the function:
Public Function authConnect() As Boolean
Dim dbserver As String
Dim dbuser As String
Dim dbpass As String
dbserver = My.Settings.dbserver.ToString
dbuser = My.Settings.dbuser.ToString
dbpass = My.Settings.dbpass.ToString
conn = New MySqlConnection
myConnString = "server=" & dbserver & ";" & "user id=" & dbuser & ";" & "password=" & dbpass & ";" & "database=rtadmin"
Dim myCommand As New MySqlCommand
Dim myAdapter As New MySqlDataAdapter
Dim myData As New DataTable
Dim myDataReader As New MySqlDataReader
Dim query As String
myCommand.Parameters.Add(New MySqlParameter("?Username", login_usr_txt.Text))
myCommand.Parameters.Add(New MySqlParameter("?Password", login_pass_txt.Text))
query = "select * from users where user = ?Username and passwd = ?Password"
conn.ConnectionString = myConnString
Try
conn.Open()
Try
myCommand.Connection = conn
myCommand.CommandText = query
myAdapter.SelectCommand = myCommand
myDataReader = myCommand.ExecuteReader
If myDataReader.HasRows() Then
MessageBox.Show("You've been logged in.", "RT Live! Information", MessageBoxButtons.OK, MessageBoxIcon.Information)
End If
Catch ex As Exception
End Try
Catch ex As Exception
End Try
End Function
The function is not yet complete, there are a few other things that need to be done before launching the application, since I'm using a MessageBox to display the result of the login attempt.
The error that I'm getting is the foll开发者_Go百科owing:
Error 1 'MySql.Data.MySqlClient.MySqlDataReader.Friend Sub New(cmd As MySql.Data.MySqlClient.MySqlCommand, statement As MySql.Data.MySqlClient.PreparableStatement, behavior As System.Data.CommandBehavior)' is not accessible in this context because it is 'Friend'. C:\Users\Mario\documents\visual studio 2010\Projects\Remote Techs Live!\Remote Techs Live!\Login.vb 43 13 Remote Techs Live!
Any ideas?
It makes no sense to try to create a MySqlDataReader and then throw it away!
First you do this to attempt to create a reader:
Dim myDataReader As New MySqlDataReader
Then later you attempt to throw that away when you do this:
myDataReader = myCommand.ExecuteReader
Just remove the New from your initial declaration. I suspect that the constructor for the MySqlDataReader is not publicly accessible.
You could try the .AddWithValue instead of .Add.
For example:
cmd.Parameters.AddWithValue("?Username", login_usr_txt.Text)
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