I have done some developments in .Net and PHP.
There is a things I like .Net , rather than PHP.
That is the component-based design.
.Net allows me to use component-based design.
I can built the system part by part.
I have tested a search engine,PhpDig.
That is quite good.
It has a spider and search page.
Moreover, it supports templates.
It got most of functions I need.
But , at this stage , it is not able spider chinese web sites.