Thank you for the reply, Pascal.
It is T-spline surface in first pic, and box mode in second pic. I should use T-spline component to show you, sorry.
When i select all control points in Rhino it was 2332 points, but in grasshopper it was 2243.
Now i realize what vertices or points in the grasshopper component output doesn’t mean control points. Thank you.
I want to use ghpython in grasshopper to build two component, one is to extrude t-spline, the other is retopo(projection) tool which can apply on whole geometry and set the error limit. So only Rhinoscript can help me access and edit the control point data, is that right?