c# - Dynamic Object - How to tell if a property is defined? -


i have dynamic object looks follows:

this.chartdetails.chart

'chart' dynamic. want see if dynamic property exists on chart named leftyaxis. best way on dynamic objects?

i don't think duplicate of how detect if property exists on expandoobject? because doesn't discuss best method dynamic objects.

bool isdefined = false; object axis = null; try {     axis = this.chartdetails.chart.leftyaxis;     isdefined = true; } catch(runtimebinderexception) { }

this happens @ runtime in first place. (when access property 'dynamic' piece of things happens when first-chance exception gets handled object's override of dynamicobject's trygetmember , trysetmember

some objects (like expandoobject) dictionaries under hood , can check them directly follows:

bool isdefined = ((idictionary<string, object>)this.chartdetails.chart)     .containskey("leftyaxis");

basically: without knowing actual type chartdetails.chart (if it's expandoobject plain ol' subclass of object or subclass of dynamicobject) there's no way besides try/catch above. if wrote code chartdetails , chart or have access source code can determine methods exist object , use check.


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