Issue: 

What is dimension associativity, and how to set dimension associativity?

Cause: 

Dimension associativity links dimensions to geometric objects.
By snapping to the endpoints of a line or selecting the line directly for dimensioning, the dimension value will automatically update when the line length is changed by dragging its grips.

Solution:

Whether a dimension is associative can be controlled by the variable DIMASSOC.


CN Solution★中望CAD标注关联有什么作用
JP Solution


★What is the function of ZWCAD dimension associativity：https://confluence.zwcad.com/pages/viewpage.action?pageId=315655575