Crear hash md5

Imports System.Security.Cryptography
Imports System.Text

Public Class getmd5

    Public Function getmd5hash(ByVal md5Hash As MD5, ByVal input As String) As String
        Dim data As Byte() = md5Hash.ComputeHash(Encoding.UTF8.GetBytes(input))
        Dim sBuilder As New StringBuilder()
        Dim i As Integer
        For i = 0 To data.Length - 1
            sBuilder.Append(data(i).ToString("x2"))
        Next i
        Return sBuilder.ToString()
    End Function
End Class

Private Sub btnok_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnok.Click
        Try
            Dim bc_getmd5 As New getmd5
            Dim source As String = tbdtefolioclave.Text.Trim
            Dim hash As String = ""
            Using md5hash As MD5 = MD5.Create()
                hash = bc_getmd5.getmd5hash(md5hash, source)
            End Using
            tbmd5.Text = hash
        Catch ex As Exception
            MessageBox.Show(ex.ToString)
        End Try
    End Sub

Ejemplo2
'dte+folio+clave
Dim source As String = "33" & "123" & "123456"
Dim hash As String = getHashMd5(source) 'Resultado: 2492f78aa4119e8d5c545ce9006f56b1


Public Function getHashMd5(ByVal stringSource As String) As String
        Using md5hash As MD5 = MD5.Create
            Dim data As Byte() = md5hash.ComputeHash(Encoding.UTF8.GetBytes(stringSource))
            Dim sBuilder As New StringBuilder()
            Dim i As Integer
            For i = 0 To data.Length - 1
                sBuilder.Append(data(i).ToString("x2"))
            Next i
            Return sBuilder.ToString()
        End Using
    End Function




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