vb.net - How to split string, apply function to every part and rejoin back without loops in .NET? -

i perform these actions inside single evaluation, if possible:

1. split string input parts according separator separator
2. apply function fnc(string) -> string every part
3. rejoin parts string result using same separator separator

that's all.

the best figure out (this in vb)

result = input.split(separator).aggregate(string.empty,             function(result, part) _                 result & if(result = string.empty, string.empty, separator) &                 fnc(part)) 

as can see, ugly because

• aggregate() needs initialization in 1st parameter (if aggregate() used without first parameter, doesn't call fnc() 1st element of array)

• this approach forces if() usage, otherwise separator added start of result

i experimented using select() , selectmany() on array created through split(), when apply string.join() on result, i'm getting cast error(!) during runtime (build works ok) , not understand why.

here effective form crashes during runtime:

result = string.join(separator, input.split(separator).selectmany(function(part) fnc(part))) 

with exception:

 system.invalidcastexception: unable cast object of type 'd__14`2[system.string,system.char]' type 'system.string[]'. 

could please suggest better approach evaluation? if can select() , selectmany() made working string.join()... or there other effective way?

feel free respond in vb or c#.

edit: how can done, not how readable such code might someone. lambda expressions used here alien many programmers. know how classic approach problem looks - foreach helper variables around...

after additional thinking , trying i've found out simple solution exists:

result = string.join(separator,                      input.split(separator).select(                      function(part) fnc(part)).toarray()) 

clean , effective!

so select() approach mentioned in question way working result. adding toarray() result did trick.

thank effort!