Dear ,i have used the PIE.htc.However,i find the size of the PIE.htc is too large,i just want the border-radius attribute only.i want to ask how can i build a new htc myself with the build.xml where on git

Documentation to the rescue: http://css3pie.com/documentation/buildi ... om-source/

thank you very much! But this way seems to build a whole htc file, not parts of the htc file

What do you mean by "parts of the HTC file"? If you are wanting to try to exclude parts of the code, then that's something you're going to have to do on your own by digging into the code and modifying it. There's no such thing as feature-specific builds (yet).