Imports System.Data
Imports System.Data.SqlClient

Public Class frmLogin
    Dim userName As String
    Dim extrainfo As String


     Private Sub btnLogin_Click(sender As Object, e As EventArgs) Handles                   btnLogin.Click
      If ConnectToSQL() Then

        Dim frm As New frmQuality(userName, extrainfo)
        Me.Hide()
        frm.Show()
        Me.Close()

    End If



     End Sub



Private Function ConnectToSQL() As Boolean

    Dim con As New SqlConnection
    Dim cmd As New SqlCommand
    Dim dbPassword As String
    Dim enteredPasswrd As String
    ' Dim userName As String

    Try



        con.ConnectionString = "Data Source "

        con.Open()

        cmd.Connection = con

        cmd.CommandText = " SELECT  UserName, Password, extrainfo  FROM  users WHERE   (UserName like '" & "%" & txtUsername.Text.ToLower() & "%" & "' )"



        Dim lrd As SqlDataReader = cmd.ExecuteReader()
        If lrd.HasRows Then
            While lrd.Read()

                'Do something here
                dbPassword = lrd("Password").ToString()
                userName = lrd("UserName").ToString()
                extrainfo = lrd("assigned_ei").ToString()


                enteredPasswrd = txtPassword.Text()

                If dbPassword.Trim() = enteredPasswrd And userName.TrimEnd(vbCrLf.ToCharArray).ToLower() = txtUsername.Text.ToLower() Then


                    Return True

                    'Clear all fields
                    txtPassword.Text = ""
                    txtUsername.Text = ""
                Else
                    MsgBox("Incorrect Password")
                End If

            End While

        Else
            MessageBox.Show("Username and Password do not match..", "Authentication Failure", MessageBoxButtons.OK, MessageBoxIcon.Exclamation)
            'Clear all fields
            txtPassword.Text = ""
            txtUsername.Text = ""
        End If

        Return False

    Catch ex As Exception
        MessageBox.Show("Error while connecting to SQL Server." & ex.Message)

    Finally
        con.Close() 'Whether there is error or not. Close the connection.

    End Try

End Function

Private Sub frmLogin_Load(sender As Object, e As EventArgs) Handles MyBase.Load
    txtUsername.Focus()

End Sub

 End Class

Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load

    Dim con As New SqlConnection
    Dim cmd As New SqlCommand

    Try


        con.ConnectionString = "Data Source = location"

        con.Open()

        cmd.Connection = con

        cmd.CommandText = " SELECT *  FROM  table WHERE adduser = '" & user & "'"

        Dim lrd As SqlDataReader = cmd.ExecuteReader()
        If lrd.HasRows Then
            While lrd.Read()

            End While
        End If



    Catch ex As Exception
        MessageBox.Show("Error while connecting to SQL Server." & ex.Message)

    Finally
        con.Close() 'Whether there is error or not. Close the connection.

    End Try



End Sub