Public Class Form1
    Dim iUno As Integer = 15
    Dim iDos As Integer = 39
    Dim iResult As Integer

    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        TextBox1.Text = iUno
        TextBox2.Text = iDos
    End Sub

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim i As String, j As Single
        i = TextBox1.Text
        j = Convert.ToSingle(i)
        Label1.Text = iResult.ToString
    End Sub
End Class