vb.net - Dynamic method calling in VB without reflection -

i want format numeric type using method call so:

option infer on option strict off imports system.runtime.compilerservices  namespace gpr     module gprextensions         <extension()>         public function togprformattedstring(value) string             ' use vb's dynamic dispatch assume value numeric             dim d double = cdbl(value)             dim s = d.tostring("n3")             dim dynamicvalue = value.tostring("n3")             return dynamicvalue         end function     end module end namespace 

now, various discussions around web (vb.net equivalent c# 'dynamic' option strict on, dynamic keyword equivalent in vb.net?), think code work when passed numeric type (double, decimal, int, etc). doesn't, can see in screenshot:

i can explicitly convert argument double , .tostring("n3") works, calling on supposedly-dynamic value argument fails.

however, can in c# following code (using linqpad). (note, compiler won't let use dynamic parameter in extension method, maybe part of problem.)

void main() {     console.writeline (1.togprformattedstring()); }  internal static class gprextensions {     public static string togprformattedstring(this object o)     {         // use vb's dynamic dispatch assume value numeric         var value = o dynamic;         double d = convert.todouble(value);         var s = d.tostring("n3").dump("double tostring");         var dynamicvalue = value.tostring("n3");         return dynamicvalue;     } } 

so gives? there way in vb call method dynamically on argument function without using reflection?

to explicitly answer "is there way in vb call method dynamically on argument function without using reflection?":

edit: i've reviewed il disassembly (via linqpad) , compared code of callbyname (via reflector) , using callbyname uses same amount of reflection normal, option strict off late binding.

so, complete answer is: can option strict off object references, except method you're trying exists on object itself, can use callbyname same effect (and, in fact, doesn't need option strict off).

dim dynamicvalue = callbyname(value, "tostring", calltype.method, "n3") 

nb not equivalent late binding call, must cater possibility "method" a(n indexed) property, calls equivalent of:

dim dynamicvalue = callbyname(value, "tostring", calltype.get, "n3") 

for other methods, double.compareto.

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details

your problem here object.tostring() exists , code not attempting dynamic dispatch, rather array index lookup on default string.chars property of string result value.tostring() call.

you can confirm happening @ compile time trying value.tostring(1,2), prefer attempt runtime lookup 2 parameter tostring, in fact fails with

too many arguments 'public readonly default property chars(index integer) char'

at compile time.

you can confirm other non-shared object methods called directly callvirt, relying upon overrides available, not dynamic dispatch calls microsoft.visualbasic.compilerservices.newlatebinding namespace, if review compiled code in il.