Is it possible to define ECProperty as enum type?

Jan Šlegr said:

is it possible (and if yes, is there an example available) to define ECProperty as enum type

Hidden in MicroStation CONNECT Update 7 are Pick Lists.  In that Update I don't think that they were intended to be publicly visible.  Perhaps we'll see more in Update 8.

See Krister Surell's post about Picklists and C#.  He obviously spotted something that I missed!

AFAIK all ECProperties (and hence Item Types) are ultimately XML data.  There are structures such as ValueMaps (see the delivered EC Schemas) that could be interpreted as a C#/C++ enum,  but there's no way that I know of to convert a ValueMap to an enum at run-time.

I'm relatively certain the new "pick lists" are only usable with Item Types (created in MicroStation's Item Types dialog), not general ECSchemas. I could be wrong.

However ECSchemas have for years supported custom attributes which behave like enums and are displayed to the user as a pick list in a drop-down when editing property values. For example, to define a "widget size" property with allowable values of Small, Medium, and Large:

<ECProperty propertyName="WidgetSize" typeName="int" displayLabel="Widget Size">
    <ECCustomAttributes>
        <StandardValues xmlns="EditorCustomAttributes.01.00">
            <ValueMap>
                <ValueMap>
                    <Value>0</Value>
                    <DisplayString>Small</DisplayString>
                </ValueMap>
                <ValueMap>
                    <Value>1</Value>
                    <DisplayString>Medium</DisplayString>
                </ValueMap>
                <ValueMap>
                    <Value>2</Value>
                    <DisplayString>Large</DisplayString>
                </ValueMap>
            </ValueMap>
        </StandardValues>
    </ECCustomAttributes>
</ECProperty>

Regards,

Paul

Thanks, Paul! This gets me 85% of the way there, which is enough for a working solution for my project. What I'm now hacking away at is to define a similar structure to a "ValueMap" which enables me to define their "Value" as a string as opposed to an integer, so that when users enter in a value not predefined, it will not error out with "ECStandardValues TypeConverter cannot convert from System.String". Something more like:

<ECProperty propertyName="WidgetSize" typeName="string" displayLabel="Widget Size">
    <ECCustomAttributes>
        <StandardValuesString xmlns="MyOwnCustomAttributes.01.00">
            <ValueMapString>
                <ValueMapString>
                    <Value>A</Value>
                    <DisplayString>Small</DisplayString>
                </ValueMapString>
                <ValueMapString>
                    <Value>B</Value>
                    <DisplayString>Medium</DisplayString>
                </ValueMapString>
                <ValueMapString>
                    <Value>C</Value>
                    <DisplayString>Large</DisplayString>
                </ValueMapString>
            </ValueMapString>
        </StandardValuesString>
    </ECCustomAttributes>
</ECProperty>

I've been trying that, and it seems to work in the Bentley Class Editor, but when I apply the schema to an element the "Pick List" functionality isn't working.

Thanks, Paul! This gets me 85% of the way there, which is enough for a working solution for my project. What I'm now hacking away at is to define a similar structure to a "ValueMap" which enables me to define their "Value" as a string as opposed to an integer, so that when users enter in a value not predefined, it will not error out with "ECStandardValues TypeConverter cannot convert from System.String". Something more like:

<ECProperty propertyName="WidgetSize" typeName="string" displayLabel="Widget Size">
    <ECCustomAttributes>
        <StandardValuesString xmlns="MyOwnCustomAttributes.01.00">
            <ValueMapString>
                <ValueMapString>
                    <Value>A</Value>
                    <DisplayString>Small</DisplayString>
                </ValueMapString>
                <ValueMapString>
                    <Value>B</Value>
                    <DisplayString>Medium</DisplayString>
                </ValueMapString>
                <ValueMapString>
                    <Value>C</Value>
                    <DisplayString>Large</DisplayString>
                </ValueMapString>
            </ValueMapString>
        </StandardValuesString>
    </ECCustomAttributes>
</ECProperty>

I've been trying that, and it seems to work in the Bentley Class Editor, but when I apply the schema to an element the "Pick List" functionality isn't working.

This relates to what I have been asking in this thread.

It is possible (and quite easy) to create PickLists for ItemTypes but the lists are strings only. I you attach such a PickList to an Int or a Double property you will get that "ECStandardValues TypeConverter cannot convert from System.String" message.

Bentleys answer was to use  the PickListHandler class (which I have not succeded to do). I think that this kind of basic data type conversion should be done automatically. If not, the PicklLists should have a data type so they can only be attached to a matching property. Otherwise you will have a dgn file that needs some application to work since the pick lists are stored in the file but not the handler.

/Krister