Imports System.Net

Public Class Form1

    Public tecaj As Byte()             'vrijednost tečaja
    Public webKlijent As WebClient
    Public pomnozi As String
    Public spremi As New System.Text.ASCIIEncoding()
    Public uDecimal As Decimal
    Public provjera As Boolean
    Public uneseniBroj As Decimal




    Private Function dobivanjeValute(ByRef uDecimal) As Decimal

        Dim webKlijent As New WebClient()
        tecaj = webKlijent.DownloadData("http://www.hvka.org/valuta.php?q=1" + iz.Text + "=?" + u.Text)
        pomnozi = spremi.GetString(tecaj)
        uDecimal = Val(pomnozi)

        Return (uDecimal)
    End Function

    Private Sub unos_TextChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles unos.TextChanged

        If (String.IsNullOrEmpty(unos.Text)) Then
            rezultat.Text = ""
        End If

        If (IsNumeric(unos.Text) = False) Then
            rezultat.Text = ""
        End If

        If (IsNumeric(unos.Text) = False) And Not (String.IsNullOrEmpty(unos.Text)) Then
            kriviUnos.Enabled = True
        Else
            If (unos.Text = "") Then
                kriviUnos.Enabled = False
            End If
            If Not (unos.Text = "") Then
                uneseniBroj = unos.Text
            End If
        End If


    End Sub



    Private Sub pretvori_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles pretvori.Click


        If (unos.Text = "") Or Not (IsNumeric(unos.Text)) Then
            MsgBox("Molimo unesite valjanu vrijednost.", MsgBoxStyle.Information, "That's an error")
        End If

        If (iz.Text = u.Text) Or (String.IsNullOrEmpty(iz.SelectedItem)) Or (String.IsNullOrEmpty(u.SelectedItem)) Then
            MsgBox("Molimo odaberite odgovarajuće valute.", MsgBoxStyle.Information, "That's an error")

        Else

                                dobivanjeValute(uDecimal)
                                rezultat.Text = unos.Text * uDecimal

                            End If





    End Sub


End Class