c# - How to make .NET reflection to work with dynamically generated objects? -


this question has answer here:

look @ following example:

void main() {     // approach 1: anonymous type     var myobject = new {         property1 = "propertyvalue1"     };      // works: properties contains "property1"     var properties = myobject.gettype().getproperties();      // approach 2: expando object     dynamic myobject2 = new expandoobject();     myobject2.property1 = "propertyvalue1";      // not work: properties2 null or empty     var properties2 = myobject2.gettype().getproperties(); }

what want make type.getproperties() work on dynamically generated type. understand why works in approach 1 , not 2. actually, in approach 1, compiler has oportunity generate anonymous type looks named type. in approach 2, however, compile time type expandoobject, reflection doesn't work properly.

how create runtime object, dynamic , work reflection, getproperties method?

edit

thanks answers, understand , know how keys , values expandoobject.. problem need pass dynamically created instance method, outside control will, in turn, call getproperties() on instance.

in order values via reflection dynamically-constructed type, you'll need use reflection.emit. less ideal requires emit msil. if use case requires simple property access, may feasible, though ill-advised.

here's simple, lightly-tested, type builder uses reflection.emit:

    public static class typebuilderutil {         public static type builddynamictype() {             var typebuilder = createtypebuilder( "dynamictype" );             createproperty( typebuilder, "property1", typeof ( string ) );              var objecttype = typebuilder.createtype();             return objecttype;         }          private static typebuilder createtypebuilder( string typename ) {             var assemblybuilder = appdomain.currentdomain.definedynamicassembly( new assemblyname( "dynamicassembly" ), assemblybuilderaccess.run );             var modulebuilder = assemblybuilder.definedynamicmodule( "dynamicmodule" );             var typebuilder = modulebuilder.definetype( typename,                                                         typeattributes.public | typeattributes.class | typeattributes.autoclass | typeattributes.ansiclass | typeattributes.beforefieldinit | typeattributes.autolayout                                                         , null );             return typebuilder;         }          private static void createproperty( typebuilder typebuilder, string propertyname, type propertytype ) {             var backingfieldbuilder = typebuilder.definefield( "_" + propertyname, propertytype, fieldattributes.private );             var propertybuilder = typebuilder.defineproperty( propertyname, propertyattributes.hasdefault, propertytype, null );             // build setter             var gettermethodbuilder = typebuilder.definemethod( "get_" + propertyname, methodattributes.public | methodattributes.specialname | methodattributes.hidebysig, propertytype, type.emptytypes );             var getteril = gettermethodbuilder.getilgenerator();             getteril.emit( opcodes.ldarg_0 );             getteril.emit( opcodes.ldfld, backingfieldbuilder );             getteril.emit( opcodes.ret );              // build setter             var settermethodbuilder = typebuilder.definemethod( "set_" + propertyname, methodattributes.public | methodattributes.specialname | methodattributes.hidebysig, null, new[] {propertytype} );             var setteril = settermethodbuilder.getilgenerator();             setteril.emit( opcodes.ldarg_0 );             setteril.emit( opcodes.ldarg_1 );             setteril.emit( opcodes.stfld, backingfieldbuilder );             setteril.emit( opcodes.ret );              propertybuilder.setgetmethod( gettermethodbuilder );             propertybuilder.setsetmethod( settermethodbuilder );         }     }

you create type, populate such:

        var mytype = typebuilderutil.builddynamictype();         var myobject = activator.createinstance( mytype );          // set value         var propertyinfo = myobject.gettype().getproperty( "property1", bindingflags.instance | bindingflags.public );         propertyinfo.setvalue( myobject, "propertyvalue", null );

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