Public Class Form1
Public Property f2 As Form2
Private Sub listBox1_SelectedIndexChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles listBox1.SelectedIndexChanged
f2.dataGridView1(columnIndex, rowIndex).Value = ค่าที่จะให้แสดง
f2.textBox1.Text = ค่าที่จะให้แสดง
End Sub
End Class
Public Class Form2
Private Sub Form2_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load
Form1.f2 = Me
Form1.ShowDialog() ' or Form1.Show()
End Sub
End Class