Connect Access DB to Windows Form

'هذا كود الاضافة

        If TextBox1.Text = "" Or TextBox2.Text = "" Or TextBox3.Text = "" Or TextBox4.Text = "" Or TextBox5.Text = "" Then
            MsgBox("Please Enter All Informations...", MsgBoxStyle.Critical, Title:="Error")
        Else
            Try
                Dim conn As New OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" & My.Application.Info.DirectoryPath.ToString() & "\Database.accdb;")
                Dim insert As String = "Insert into Users values('" & TextBox1.Text & "','" & TextBox2.Text & "','" & TextBox3.Text & "','" & TextBox4.Text & "','" & TextBox5.Text & "');"
                Dim cmd As New OleDbCommand(insert, conn)
                conn.Open()
                cmd.ExecuteNonQuery()
                MsgBox("New User Added Successfully", MsgBoxStyle.Information, Title:="Add New User Sucess")
                Me.Close()
            Catch ex As Exception
                MsgBox("Error", MsgBoxStyle.Critical, Title:="Error")
            End Try
        End If



'Public Class Form1 وهذا الكود ضعه فوق كلمة
Imports System.Data.OleDb
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'هذا كود التعديل

            Dim cmd As New OleDbCommand
            Dim i As Integer
            con.Open()
            With cmd
                .Connection = con
                .CommandText = "UPDATE Sales SET ItemName = '" & ComboBox1.Text & "',ItemPrice = '" & TextBox1.Text & "',Quantity = '" & TextBox2.Text & "',Total = '" & TextBox3.Text & "',DateofSale = '" & TextBox4.Text & "'"
                i = .ExecuteNonQuery
            End With
            If i > 0 Then
                MsgBox("Update Record")
            End If
            con.Close()

'End Sub هذا فنكشن حطه تحت اي كلمة

    Public Function jokendb() As OleDb.OleDbConnection
        Return New OleDb.OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" & Application.StartupPath & "\Database.accdb")
    End Function

'Public Class Form1 وهذا الكود حطه تحت كلمة

Public con As OleDb.OleDbConnection = jokendb()
'======================================================================================================================
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'هذا كود الحذف

        Dim con As OleDbConnection
        Dim com As OleDbCommand
        con = New OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" & My.Application.Info.DirectoryPath.ToString() & "\Database.accdb")
        com = New OleDbCommand("delete from Users where Username = @Username", con)
        con.Open()
        com.Parameters.AddWithValue("@Username", TextBox1.Text)
        com.ExecuteNonQuery()
        MsgBox("User Deleted Sucessfully.", MsgBoxStyle.Information, Title:="User Deleted")
        con.Close()