Grid view exporting with style

[trinh]

I have grid that cell content is styling( foregroundcolor, FontStyle, Underline,...).
When i export the grid data to excel, the foregroundColor, FontFamily, ... is Ok on excel file.
But i can not find the way to set the FontStyle and Underline of cell in exported excel file.

I am using the custom of ElementExporting event.

So, how to do this?