this part od codes what say?

[irandoct]

Hi,
i'm not familiar with visual c#! i have a program source! i want to know what says this part of codes:

private void PBOk_Click(object eventSender, EventArgs eventArgs)
{
    if (Strings.Len(Strings.Trim(this.EnCode.Text)) == 0)
    {
        Interaction.MsgBox("A registration code must be entered.", MsgBoxStyle.ApplicationModal, MODULE11.Security.Title);
    }
    else
    {
        string str2;
        string str3;
        string str4;
        string str5;
        string[] strArray;
        this.EnCode.Text = this.EnCode.Text.Trim();
        string s = "";
        short num2 = (short) Strings.Len(this.EnCode.Text);
        for (short i = 1; i <= num2; i = (short) (i + 1))
        {
            if (Strings.Mid(this.EnCode.Text, i, 1) != "-")
            {
                s = s + Strings.Mid(this.EnCode.Text, i, 1);
            }
        }
        if (this.AddModule)
        {
            if (MODULE11.Security.AddModule(s))
            {
                Interaction.MsgBox("Thank you for purchasing. Please restart " + MODULE11.Security.Title + " for the changes to take place.", MsgBoxStyle.ApplicationModal, MODULE11.Security.Title);
                this.Register = true;
                this.Close();
            }
            else
            {...