Dimension Value Ovveride

[Anonymous]

Hi all,

Tell me please, how to override value for Dimension from API (C#)?

Thanks.

[rosalesduquej]

Dear Aleksandr,

Have you tried using Dimension.ValueOverride Property

http://revitapisearch.com/html/4560ec6c-5aab-fcae-a64c-6f939ae06d94.htm

Hope it helps. 

Cheers,

[Anonymous]

Thank you Jaime,

I have seen that, but I do not know how to apply... Tried in different ways, sometimes Revit crashes. It would be nice to get a ready example.

Thanks.

[BobbyC.Jones]

I have also observed a Revit crash when accessing a DimensionSegment.ValueOverride property via a System.AccessViolationException when the .ValueOverride property has no value.  It will also crash if the .Below, .Above, .Prefix, or .Suffix properties are accessed when they contain no value.

I found a workaround on stackoverflow, How to handle AccessViolationException, which has links to some addition articles on MSDN.

Basically you wrap reads to those properties in a Try/Catch block and decorate the calling method with a [HandleProcessCorruptedStateExceptions] attribute  (The stackoverflow link has other solutions but this is the only one that I've tried).

        [HandleProcessCorruptedStateExceptions]
        private void GetOverride(Dimension singleSegmentDimension)
        {
            try
            {
                ValueOverride = singleSegmentDimension.ValueOverride;
            }
            catch (System.AccessViolationException ex)
            {
                //Handle the scary "Attempted to read or write protected memory. This is often an indication that other memory is corrupt." message...
            }
        }

[Anonymous]

Thanks Bobby, but... I want write different value to Value Override of Dimension.

[BobbyC.Jones]

I haven't tested yet, but this may have been addressed in 2016 SP2 per the release notes.

• Improves stability when DimensionSegment ValueOverride API is called when the dimension value was not overridden.

[tdaniel]

Does the crash happen on Single or Multi-Segment Dimensions or both?

[BobbyC.Jones]

Both.

<unrelated side rant>

I REALLY HATE that we have to handle single and multiple segments differently!  Sorry, but sometimes you just gotta let that stuff out  🙂