' Not all fonts support the same styles. This function takes in ' input a font family and a font style, and returns a font style' which is safe for that particular font family, by removing' the styles that are not supported'' Example:'   GetSafeStyleForFontFamily(richTextBox1.SelectionFont.FontFamily,'  '     richTextBox1.SelectionFont.Style)Public Function GetSafeStyleForFontFamily(ByVal fontFam As FontFamily, _    ByVal style As FontStyle) As FontStyle    ' remove the styles not supported    If (style And FontStyle.Regular) = FontStyle.Regular Then        ' if the regular style is currently present, but not supported         ' by the new font family, remove it        If Not fontFam.IsStyleAvailable(FontStyle.Regular) Then            style = style And Not FontStyle.Regular        End If    End If    ' do the same for bold, italic and underline    If (style And FontStyle.Bold) = FontStyle.Bold Then        If Not fontFam.IsStyleAvailable(FontStyle.Bold) Then            style = style And Not FontStyle.Bold        End If    End If    If (style And FontStyle.Italic) = FontStyle.Italic Then        If Not fontFam.IsStyleAvailable(FontStyle.Italic) Then            style = style And Not FontStyle.Italic        End If    End If    If (style And FontStyle.Underline) = FontStyle.Underline Then        If Not fontFam.IsStyleAvailable(FontStyle.Underline) Then            style = style And Not FontStyle.Underline        End If    End If    If (style And FontStyle.Strikeout) = FontStyle.Strikeout Then        If Not fontFam.IsStyleAvailable(FontStyle.Strikeout) Then            style = style And Not FontStyle.Strikeout        End If    End If    Return styleEnd Function