Above element

ba ranh said:

I hope Mr. Jan and friends will help

Do I see standard set of information shared? No! Looks like you're kidding us.

And for the discussed topic, the answer can be different depending on context (MicroStation format, DGN format, model dimension...).

ba ranh said:

VBA or any programming language

In MicroStation, the main solution does not depend on API.

ba ranh said:

I want the blue line to be above the yellow line

The standard solution is to use element priority. The recommended way is to assign priority per level, but it can be assigned also individually to elements. It requires 2D file (because in 3D it does not make sense) and DGN V8 format.

Regards,

  Jan

ba ranh said:

The green line is below the yellow cell
I want the blue line to be above the yellow line

ba ranh said:

After searching for the keyword 'priority', I found instructions

MicroStation element (and level) priority has been part of the product since MicroStation XM.  Another term for that is Z-order, used for example in 2D drawing tools such as Adobe Illustrator. 

It's poor practise to uses words such as above and below, because MicroStation is a 3D tool, and those words mean something in a 3D model.  Z-order also introduces confusion in MicroStation because it means something different in a 3D model.

ba ranh said:

I use MicroStation V8i, DGN 2D V7 up to V8

As MaryB comments, all the above refers to DGN files created by MicroStation XM and later. Earlier versions of MicroStation V8 don't support element priority, nor do V7 DGN files.