login.vb

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Imports System.Data.SqlClient
Imports System.Threading.Thread
Imports System.Threading.Monitor


Public Class login
    Inherits System.Windows.Forms.Form

    Public cn As New SqlConnection("server=localhost;database=lms;uid=sa;password=;")
    Public da As SqlDataAdapter
    Public ds As DataSet
    Public cmd As New SqlCommand
    Public t1 As New Threading.Thread(AddressOf connect)
    Public Shared state As Integer = 0


#Region " Windows Form Designer generated code "

    Public Sub New()
        MyBase.New()

        'This call is required by the Windows Form Designer.
        InitializeComponent()

        'Add any initialization after the InitializeComponent() call

    End Sub

    'Form overrides dispose to clean up the component list.
    Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
        If disposing Then
            If Not (components Is Nothing) Then
                components.Dispose()
            End If
        End If
        MyBase.Dispose(disposing)
    End Sub

    'Required by the Windows Form Designer
    Private components As System.ComponentModel.IContainer

    'NOTE: The following procedure is required by the Windows Form Designer
    'It can be modified using the Windows Form Designer.  
    'Do not modify it using the code editor.
    Friend WithEvents txt_username As System.Windows.Forms.TextBox
    Friend WithEvents txt_password As System.Windows.Forms.TextBox
    Friend WithEvents btn_ok As System.Windows.Forms.Button
    Friend WithEvents btn_cancel As System.Windows.Forms.Button
    Friend WithEvents lbl_username As System.Windows.Forms.Label
    Friend WithEvents lbl_password As System.Windows.Forms.Label
    Friend WithEvents Label1 As System.Windows.Forms.Label
    Friend WithEvents ProgressBar1 As System.Windows.Forms.ProgressBar
    <System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
        Me.txt_username = New System.Windows.Forms.TextBox
        Me.txt_password = New System.Windows.Forms.TextBox
        Me.btn_ok = New System.Windows.Forms.Button
        Me.btn_cancel = New System.Windows.Forms.Button
        Me.lbl_username = New System.Windows.Forms.Label
        Me.lbl_password = New System.Windows.Forms.Label
        Me.Label1 = New System.Windows.Forms.Label
        Me.ProgressBar1 = New System.Windows.Forms.ProgressBar
        Me.SuspendLayout()
        '
        'txt_username
        '
        Me.txt_username.Font = New System.Drawing.Font("Tahoma", 8.25!, System.Drawing.FontStyle.Bold, System.Drawing.GraphicsUnit.Point, CType(0, Byte))
        Me.txt_username.Location = New System.Drawing.Point(119, 32)
        Me.txt_username.Name = "txt_username"
        Me.txt_username.ReadOnly = True
        Me.txt_username.Size = New System.Drawing.Size(104, 21)
        Me.txt_username.TabIndex = 3
        Me.txt_username.Text = "Librarian"
        '
        'txt_password
        '
        Me.txt_password.Font = New System.Drawing.Font("Tahoma", 8.25!, System.Drawing.FontStyle.Bold, System.Drawing.GraphicsUnit.Point, CType(0, Byte))
        Me.txt_password.Location = New System.Drawing.Point(119, 64)
        Me.txt_password.MaxLength = 10
        Me.txt_password.Name = "txt_password"
        Me.txt_password.PasswordChar = Microsoft.VisualBasic.ChrW(42)
        Me.txt_password.Size = New System.Drawing.Size(104, 21)
        Me.txt_password.TabIndex = 0
        Me.txt_password.Text = ""
        '
        'btn_ok
        '
        Me.btn_ok.Font = New System.Drawing.Font("Tahoma", 8.25!, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, CType(0, Byte))
        Me.btn_ok.Location = New System.Drawing.Point(79, 104)
        Me.btn_ok.Name = "btn_ok"
        Me.btn_ok.Size = New System.Drawing.Size(56, 23)
        Me.btn_ok.TabIndex = 1
        Me.btn_ok.Text = "OK"
        '
        'btn_cancel
        '
        Me.btn_cancel.Font = New System.Drawing.Font("Tahoma", 8.25!, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, CType(0, Byte))
        Me.btn_cancel.Location = New System.Drawing.Point(151, 104)
        Me.btn_cancel.Name = "btn_cancel"
        Me.btn_cancel.Size = New System.Drawing.Size(56, 23)
        Me.btn_cancel.TabIndex = 2
        Me.btn_cancel.Text = "Cancel"
        '
        'lbl_username
        '
        Me.lbl_username.AutoSize = True
        Me.lbl_username.Font = New System.Drawing.Font("Tahoma", 8.25!, System.Drawing.FontStyle.Bold, System.Drawing.GraphicsUnit.Point, CType(0, Byte))
        Me.lbl_username.ForeColor = System.Drawing.Color.Navy
        Me.lbl_username.Location = New System.Drawing.Point(42, 32)
        Me.lbl_username.Name = "lbl_username"
        Me.lbl_username.Size = New System.Drawing.Size(72, 17)
        Me.lbl_username.TabIndex = 4
        Me.lbl_username.Text = "Username : "
        '
        'lbl_password
        '
        Me.lbl_password.AutoSize = True
        Me.lbl_password.Font = New System.Drawing.Font("Tahoma", 8.25!, System.Drawing.FontStyle.Bold, System.Drawing.GraphicsUnit.Point, CType(0, Byte))
        Me.lbl_password.ForeColor = System.Drawing.Color.Navy
        Me.lbl_password.Location = New System.Drawing.Point(47, 64)
        Me.lbl_password.Name = "lbl_password"
        Me.lbl_password.Size = New System.Drawing.Size(70, 17)
        Me.lbl_password.TabIndex = 5
        Me.lbl_password.Text = "Password : "
        '
        'Label1
        '
        Me.Label1.AutoSize = True
        Me.Label1.BackColor = System.Drawing.Color.Silver
        Me.Label1.Font = New System.Drawing.Font("Verdana", 9.75!, System.Drawing.FontStyle.Bold, System.Drawing.GraphicsUnit.Point, CType(0, Byte))
        Me.Label1.ForeColor = System.Drawing.Color.DarkRed
        Me.Label1.Location = New System.Drawing.Point(16, 152)
        Me.Label1.Name = "Label1"
        Me.Label1.Size = New System.Drawing.Size(190, 19)
        Me.Label1.TabIndex = 5
        Me.Label1.Text = "Connecting...please wait"
        '
        'ProgressBar1
        '
        Me.ProgressBar1.Location = New System.Drawing.Point(16, 176)
        Me.ProgressBar1.Name = "ProgressBar1"
        Me.ProgressBar1.Size = New System.Drawing.Size(248, 12)
        Me.ProgressBar1.TabIndex = 6
        '
        'login
        '
        Me.AcceptButton = Me.btn_ok
        Me.AutoScaleBaseSize = New System.Drawing.Size(5, 13)
        Me.BackColor = System.Drawing.Color.Silver
        Me.ClientSize = New System.Drawing.Size(280, 205)
        Me.Controls.Add(Me.ProgressBar1)
        Me.Controls.Add(Me.lbl_password)
        Me.Controls.Add(Me.lbl_username)
        Me.Controls.Add(Me.btn_cancel)
        Me.Controls.Add(Me.btn_ok)
        Me.Controls.Add(Me.txt_password)
        Me.Controls.Add(Me.txt_username)
        Me.Controls.Add(Me.Label1)
        Me.MaximizeBox = False
        Me.MinimizeBox = False
        Me.Name = "login"
        Me.StartPosition = System.Windows.Forms.FormStartPosition.CenterScreen
        Me.Text = "Login"
        Me.ResumeLayout(False)

    End Sub

#End Region

    Private Sub btn_ok_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btn_ok.Click

        Try
            da = New SqlDataAdapter("select Pwd from user_auth", cn)
            ds = New DataSet

            'fetching user information from databse
            da.Fill(ds, "user_auth")



                If txt_password.Text <> "" Then  'blank password is not allowed

                If ds.Tables(0).Rows.Count <> 0 Then

                    'checking password
                    If txt_password.Text = ds.Tables(0).Rows(0)(0) Then

                        'enabling MDI form menus
                        Me.MdiParent.Menu.MenuItems(0).Enabled = True
                        Me.MdiParent.Menu.MenuItems(1).Enabled = True
                        Me.MdiParent.Menu.MenuItems(2).Enabled = True
                        Me.MdiParent.Menu.MenuItems(3).Enabled = True
                        Me.MdiParent.Menu.MenuItems(4).Enabled = True
                        Me.Dispose()
                    Else
                        MessageBox.Show("Wrong password,try again !!", "LMS", MessageBoxButtons.OK, MessageBoxIcon.Error)
                        txt_password.Clear()
                        txt_password.Focus()
                    End If
                Else

                    If txt_password.Text = "password" Then

                        Me.MdiParent.Menu.MenuItems(0).Enabled = True
                        Me.MdiParent.Menu.MenuItems(1).Enabled = True
                        Me.MdiParent.Menu.MenuItems(2).Enabled = True
                        Me.MdiParent.Menu.MenuItems(3).Enabled = True
                        Me.MdiParent.Menu.MenuItems(4).Enabled = True


                        cmd = New SqlCommand
                        cmd.Connection = cn
                        cmd.CommandText = "insert into user_auth values('Librarian','password');insert into options values(1,1)"
                        cmd.ExecuteNonQuery()



                        Me.Dispose()
                    Else
                        MessageBox.Show("Wrong password,try again !!", "LMS", MessageBoxButtons.OK, MessageBoxIcon.Error)
                        txt_password.Clear()
                        txt_password.Focus()
                    End If
                End If


            Else 'if password is blank set focus back to the control
                txt_password.Focus()
            End If

        Catch err As SqlException
            MessageBox.Show(err.Message, "Exception", MessageBoxButtons.OK, MessageBoxIcon.Error)

        Catch ers As System.Exception
            MessageBox.Show(ers.Message, "Exception", MessageBoxButtons.OK, MessageBoxIcon.Error)

        Finally

            'dereferencing objects
            da = Nothing
            ds = Nothing
            cmd = Nothing

        End Try
    End Sub

    Private Sub btn_cancel_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btn_cancel.Click
        End
    End Sub


    Private Sub login_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

        Me.Show()

        Application.DoEvents()

        btn_ok.Visible = False
        btn_cancel.Visible = False
        txt_password.Visible = False
        txt_username.Visible = False
        lbl_password.Visible = False
        lbl_username.Visible = False

        t1.Start()

        While (True)

            If ProgressBar1.Value <> 100 Then
                ProgressBar1.Value = ProgressBar1.Value + 10
                Threading.Thread.CurrentThread.Sleep(200)
            End If


            If state = 1 Then
                ProgressBar1.Value = 100
                Label1.Text = "Connected!"
                btn_ok.Visible = True
                btn_cancel.Visible = True
                txt_password.Visible = True
                txt_username.Visible = True
                lbl_password.Visible = True
                lbl_username.Visible = True


                Me.Size = New System.Drawing.Size(288, 180)

                Exit While
            ElseIf state = 2 Then
                Exit While
            End If
        End While

    End Sub


    Sub connect()
        Try

            cn.Open()
            state = 1

        Catch ex As System.Exception
            state = 2
            Label1.Text = "Not Connected!"
            MessageBox.Show(ex.Message, "Error", MessageBoxButtons.OK, MessageBoxIcon.Error)
            End
        End Try

    End Sub


    Private Sub login_Closing(ByVal sender As Object, ByVal e As System.ComponentModel.CancelEventArgs) Handles MyBase.Closing
        End
    End Sub

End Class