i can't draw a classical steel handrail stair in 2d autocad  .who're pro? 

Hello, if it helps, try to find an example right here in the site by entering "hand rail" in the CAD Blocks library search ( 2D and 3D existing ).

thanks philipe joseph but this problem's not simple .....my problem is ,...http://www.youtube.com/watch?v=y9hNTvh2Wds

how to creat  same them?????

Can you post an image?  Our company blocks the site you gave the link for.

Hello tuanmax, I took a look at the youtube video and it seems very well explained.
It will work if you download the lisp routine file named IRONPAT.lsp ( from where you can obtain it I don't know ) and launch the command APPLOAD to charge it and then launch the command IRONPAT.
The rest is explained in the youtube video.
I haven't tried it.
Tell us if it's OK for you or else.....
Note : That lisp routine is tranforming a rectangular pattern ( may be a block ) into a non rectangular pattern so that you can use it into a inclined stair and tranform an horizontal hand rail to be used in a stair of ( for example 12" x 6" slope ) that you enter as values during the lisp routine.
Ask for more....
 
I searched on the web and the answer is : you can download IRONPAT.lsp and STAIR.lsp with 27 US Dollars from Rayburn Drafting......philippe JOSEPH2012-10-16 12:50:21