How to refresh titleblock immediately ?

[Hui-lung.Chen]

I have an addIn that can help users input drawing's data. These data are written in custom ipropertes, which are linked to the titleblock.
My problem is that it takes time(about 5 seconds) to refresh the titleblock via drawingDocument.Update method.
But if I save the file or enter the iproperties and then exit again, the titleblock refresh immediately.
How can I refresh the titleblock quickly?

My PC:
Inventor suit 2009
XP 64bit with 8G ram
Intel® Core™ i7-870 Processor
NVIDIA Quadro FX 380

[YuhanZhang]

Can you try the Sheet.Update works for you or not?

[Hui-lung.Chen]

Unfortunately, sheet.update doesn't work in INS 2009.