CE C# Build Display Rules programmatically

salvatore montella said:

Could anyone tell me what is the exact way to build a rule condition from code?

More generally, I think we need advice on writing Expressions programmatically.  It's easy to get an Expression wrong, but hard to get diagnostic information (as you have found).

salvatore montella said:

string MyRuleCondition = $@"REFERENCE.References.Logical Name = {fieldValue}";"

It's not clear what you're writing in that statement...

• A literal string is prefixed with two special .NET modifiers $@
• The string is terminated with an additional quote after the semi-colon
• How do you assign that statement to an Expression?

Please write your actual code here so we can better understand what you have:  Use the Insert|Code button.

Hi Jon, thanks for replying.
Here is the whole procedure I wrote to create the display rule.

Thanks for your help,

Salvio

 private void DiplayRulesSampleNew()
        {
            BIM.CadInputQueue keyInCommand = ustnApp.CadInputQueue;

            DgnFile dgnFile = BM.Session.Instance.GetActiveDgnFile();
            DgnModel dgnModel = BM.Session.Instance.GetActiveDgnModel();
            DgnModelRef dgnModelRef = BM.Session.Instance.GetActiveDgnModelRef();

            string RuleStenName = "RulSet_1";
            string MyRuleCondition = @"REFERENCE.References.Logical Name = ""Attachment_1""";

            
            DisplayRuleSet displayRuleSet = new DisplayRuleSet(RuleStenName, dgnFile);
            
            DisplayRulesManager.WriteDisplayRuleSetToFile(displayRuleSet, dgnFile, true);
            DisplayRule displayRuleElement = new DisplayRule(MyRuleCondition, true, dgnFile);

            IDisplayRuleAction ruleAction = new ColorOverrideAction(5, dgnFile);
            displayRuleElement.AddAction(ruleAction);
            displayRuleSet.AddDisplayRule(displayRuleElement);
            DisplayRulesManager.WriteDisplayRuleSetToFile(displayRuleSet, dgnFile, true);

            keyInCommand.SendKeyin("MDL KEYIN CUSTOMDISPMODE DIALOG DISPLAYSTYLES");
            keyInCommand.SendKeyin(@"DISPLAYSTYLE CREATE ""DISPLAY_STYLE_BY_KEYIN""");
            keyInCommand.SendKeyin(@"MDL KEYIN VIEWCTRL CHANGE VIEW CUSTOM ""DISPLAY_STYLE_BY_KEYIN"" 1");
            keyInCommand.SendKeyin(@"DISPLAYSTYLE SETPARAM DISPLAYRULESET ""DISPLAY_STYLE_BY_KEYIN"" ""RulSet_1""");

            ustnApp.CommandState.StartDefaultCommand();


        }

Hi Salvatore,

salvatore montella said:

Here is the whole procedure I wrote to create the display rule.

In my opinion your original code and the more completed code does something different.

In the first case, at runtime, the string is:

string MyRuleCondition = "REFERENCE.References.Logical Name = Attachment_1"

whereas in the second code, the string is:

string MyRuleCondition = @"REFERENCE.References.Logical Name = ""Attachment_1"""

I have not used Display Rules API often, but I remember it's quite sensitive about quotation marks and other characters, because (unfortunately) the conditions are interpreted as text in this case.

Regards,

  Jan

Hi Salvatore,

salvatore montella said:

Here is the whole procedure I wrote to create the display rule.

In my opinion your original code and the more completed code does something different.

In the first case, at runtime, the string is:

string MyRuleCondition = "REFERENCE.References.Logical Name = Attachment_1"

whereas in the second code, the string is:

string MyRuleCondition = @"REFERENCE.References.Logical Name = ""Attachment_1"""

I have not used Display Rules API often, but I remember it's quite sensitive about quotation marks and other characters, because (unfortunately) the conditions are interpreted as text in this case.

Regards,

  Jan