inject string in MSIL at runtime

Do someone know how to inject a string in code at runtime?
I want to use it with ldstr .. but this require an address and I didn't find anything on internet that say how string are stored(and where) in MSIL...

Hey, I think pattern scanning may be your solution. Google "C++ signature/Pattern scanning tutorial" by fleep.

i don't want to find an address .. i want to put a string wherever i want .. but MSIL store string in metadata ..