テーブルでいくつかのデータを選択したいので、次のコードを使用します。
Public Class frmLogin
Private Sub OK_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnOK.Click
Dim t As New DataTable
Dim adapter As OleDbDataAdapter = New OleDbDataAdapter()
Dim cmd As OleDbCommand
Dim reader As OleDbDataReader = Nothing
Dim tuser As String = txtUsername.Text
Dim sql As String = "SELECT * FROM dosen WHERE nip=tuser"
Try
cmd = New OleDbCommand(sql, conn)
reader = cmd.ExecuteReader()
While reader.Read
MessageBox.Show(reader.GetString(0).ToString & _
vbTab & vbTab & reader.GetString(1).ToString)
End While
Finally
If reader IsNot Nothing Then reader.Close()
End Try
End Sub
しかし、reader = cmd.ExecuteReader()
行にエラーがあります。誰でも私を助けることができますか?