Public Class Main
    Private Sub GetFont()
        For Each family In FontFamily.Families
            If family.IsStyleAvailable(FontStyle.Bold) = False Then Exit For
            'family.Name
        Next family
    End Sub

    Private Sub Save()
        Dim Font = "FontName"

        Dim regVersion = Microsoft.Win32.Registry.LocalMachine.OpenSubKey("SOFTWARE\\Microsoft\\Windows NT\\CurrentVersion\\Fonts", True)
        regVersion.SetValue("Batang & BatangChe & Gungsuh & GungsuhChe (TrueType)", "")
        regVersion.SetValue("Gulim & GulimChe & Dotum & DotumChe (TrueType)", "")

        regVersion = Microsoft.Win32.Registry.LocalMachine.OpenSubKey("SOFTWARE\\Microsoft\\Windows NT\\CurrentVersion\\FontSubstitutes", True)
        regVersion.CreateSubKey("Gulim")
        regVersion.CreateSubKey("GulimChe")
        regVersion.CreateSubKey("Dotum")
        regVersion.CreateSubKey("DotumChe")
        regVersion.CreateSubKey("Batang")
        regVersion.CreateSubKey("BatangChe")
        regVersion.CreateSubKey("Gungsuh")
        regVersion.CreateSubKey("GungsuhChe")

        regVersion.SetValue("Gulim", Font)
        regVersion.SetValue("GulimChe", Font)
        regVersion.SetValue("Dotum", Font)
        regVersion.SetValue("DotumChe", Font)
        regVersion.SetValue("Batang", Font)
        regVersion.SetValue("BatangChe", Font)
        regVersion.SetValue("Gungsuh", Font)
        regVersion.SetValue("GungsuhChe", Font)
    End Sub

    Private Sub Reset()
        Dim regVersion = Microsoft.Win32.Registry.LocalMachine.OpenSubKey("SOFTWARE\\Microsoft\\Windows NT\\CurrentVersion\\Fonts", True)
        regVersion.SetValue("Batang & BatangChe & Gungsuh & GungsuhChe (TrueType)", "batang.ttc")
        regVersion.SetValue("Gulim & GulimChe & Dotum & DotumChe (TrueType)", "gulim.ttc")

        regVersion = Microsoft.Win32.Registry.LocalMachine.OpenSubKey("SOFTWARE\\Microsoft\\Windows NT\\CurrentVersion\\FontSubstitutes", True)
        regVersion.DeleteValue("Gulim", False)
        regVersion.DeleteValue("GulimChe", False)
        regVersion.DeleteValue("Dotum", False)
        regVersion.DeleteValue("DotumChe", False)
        regVersion.DeleteValue("Batang", False)
        regVersion.DeleteValue("BatangChe", False)
        regVersion.DeleteValue("Gungsuh", False)
        regVersion.DeleteValue("GungsuhChe", False)
    End Sub
End Class