membuat log in (VB.net)

pertama create design form seperti ini

kemudian create satu lagi seperti ini,ini berfungsi untuk yang mau registrasi karna blm pnya user_id sama password:

kemudian .buka Ms.Access create tabel_user *namanya terserah apaan yang penting gg pake spasi*,contohnya ni ya :

lalu kembali lagi ke MS.visual studio ,lalu add module untuk koneksi data .
ini contoh codingya:

Imports System.Data
Imports System.Data.OleDb
Module Module1
Public koneksi As New OleDbConnection
Public perintah As New OleDb.OleDbCommand
Public pembaca As OleDb.OleDbDataReader
Public Function connection()
Dim sambung As String
sambung = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source= " + Application.StartupPath + "\\db1.mdb;"
Return sambung
End Function
End Module

lalu ke design pertama dan buat coding seperti ini *ini hanya conso alias contoh soal*:
Public Class Form1


Private Sub cmdlogin_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cmdlogin.Click
koneksi.ConnectionString = connection()
koneksi.Open()
perintah.Connection = koneksi
perintah.CommandText = "SELECT username,Pasword FROM tblusername WHERE username='" & txtuser.Text & "' AND pasword='" & txtpas.Text & "'"
pembaca = perintah.ExecuteReader()

If pembaca.Read = False Then
MessageBox.Show("Nama atau password salah", "Login gagal!")
Else
MessageBox.Show("U r logged in", "Login sukses!")
End If
koneksi.Close()
End Sub

Private Sub cmdregistrasi_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cmdregistrasi.Click
registrasi.Show()

End Sub

Private Sub cmdreset_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cmdreset.Click
txtuser.Text = ""
txtpas.Text = ""


End Sub

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

End Sub
End Class




lalu buka design yang kedua tadi kemudian buat coding ini :



Public Class registrasi

Private Sub cmdtambah_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cmdtambah.Click
koneksi.Close()
koneksi.ConnectionString = connection()
koneksi.Open()
perintah.Connection = koneksi
perintah.CommandText = "SELECT username From tblusername WHERE username='" & txtuser.Text & "'"
pembaca = perintah.ExecuteReader()

If pembaca.Read = True Then
MessageBox.Show("Username sudah Terpakai,silakan gunakan userame lain", "Trickandy!")
koneksi.Close()
txtuser.Text = ""
txtpas.Text = ""
txtulangi.Text = ""
Else
koneksi.Close()
koneksi.ConnectionString = connection()
koneksi.Open()
perintah.Connection = koneksi
perintah.CommandText = "INSERT INTO tblusername (username,pasword) VALUES ( '" & txtuser.Text & "','" & txtpas.Text & "')"

perintah.ExecuteNonQuery()

koneksi.Close()
End If

End Sub

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

End Sub
End Class