[Ashir]

public void setFontFormatInRange(   MSOfficeBookMark_RU _bookMark,
                                    int                 _workSheet  = 1,
                                    boolean             _Bold       = false,
                                    boolean             _Italic     = false,
                                    boolean             _Underline  = false )
{
    #define.xlUnderlineStyleSingle(2)
    #define.xlUnderlineStyleNone(-4142)
    COM Rng, Font;

    Rng  = this.findRange(_bookMark, _workSheet);
    Font = Rng.font();
    Font.Bold(_Bold);
    Font.Italic(_Italic);
    if (_Underline)
        Font.Underline(#xlUnderlineStyleSingle);
    else
        Font.Underline(#xlUnderlineStyleNone);
}