Slope Label Expression, remove "???" Labels

[m_kingdon]

Hi all,

During the period of lockdown, I have decided to update some company template label styles.

So far I have written an expression to remove slope labels that on any flat surface.

I now want to write an expression that removes any labels outside a surface, the labels that return ???.  But how do I specify that in an expression?  My end goal is to have the labels behave like Spot Elevation of Grid labels, just with sloping arrows.

[Jeew-m]

Hi,

Are they in a grid or just random spot heights.

Can you upload a sample dwg.?

Thanks

[m_kingdon]

I can't etransmit right now, I am working from home.

But the labels I am using are surface slope labels.  Not spot elevations.  I have just copied them into a 5x5 grid over my surface.

I have added a higher res photo.

[ilia.borisov]

Unfortunately in Civil3d you cant test for Null values (like ???) so there is no way to remove it with expression.

[Jeew-m]

I am not good at expressions. But I wish this video could shed light you on something.

[m_kingdon]

Thanks, but can spot elevations so arrows pointing downhill?