DataGridView - Penjualan

Public Class Penjualan

    Private Sub cbBarang_SelectedIndexChanged(sender As Object, e As EventArgs) Handles cbBarang.SelectedIndexChanged

        If cbBarang.Text = "B001" Then

            txtNama.Text = "Spidol"

            txtHarga.Text = 23000

        ElseIf cbBarang.Text = "B002" Then

            txtNama.Text = "Buku"

            txtHarga.Text = 5000

        ElseIf cbBarang.Text = "B003" Then

            txtNama.Text = "Pulpen"

            txtHarga.Text = 3500

        Else

            MessageBox.Show("Kode barang tidak tersedia")

        End If

    End Sub

    Private Sub btnTambahkan_Click(sender As Object, e As EventArgs) Handles btnTambahkan.Click

        Dim row As String() = New String() {cbBarang.Text, txtNama.Text, txtHarga.Text, txtKts.Text, Val(txtHarga.Text) * Val(txtKts.Text)}

        DataGridView1.Rows.Add(row)

        Me.cbBarang.Text = ""

        Me.txtNama.Clear()

        Me.txtHarga.Clear()

        Me.txtKts.Clear()

    End Sub

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

        'menentukan jumlah kolom

        DataGridView1.ColumnCount = 5

        'memberi judul kolom

        DataGridView1.Columns(0).Name = "Kode Barang"

        DataGridView1.Columns(1).Name = "Nama Barang"

        DataGridView1.Columns(2).Name = "Harga"

        DataGridView1.Columns(3).Name = "Kuantitas"

        DataGridView1.Columns(4).Name = "Jumlah"

    End Sub

    Private Sub btnHitung_Click(sender As Object, e As EventArgs) Handles btnHitung.Click

        Dim i As Integer

        Dim jlh As Double = 0

        For i = 0 To Me.DataGridView1.Rows.Count - 1

            jlh = jlh + Val(Me.DataGridView1.Rows(i).Cells(4).Value)

        Next

        txtSub.Text = jlh

    End Sub

    Private Sub txtDiskon_TextChanged(sender As Object, e As EventArgs) Handles txtDiskon.TextChanged

        If Val(txtDiskon.Text) <= Val(txtSub.Text) Then

            txtGrand.Text = Val(txtSub.Text) - Val(txtDiskon.Text)

        Else

            txtGrand.Text = 0

        End If

    End Sub

    Private Sub txtBayar_TextChanged(sender As Object, e As EventArgs) Handles txtBayar.TextChanged

        If Val(txtBayar.Text) >= Val(txtGrand.Text) Then

            txtKembalian.Text = Val(txtBayar.Text) - Val(txtGrand.Text)

        Else

            txtKembalian.Text = 0

        End If

    End Sub

End Class