Stop macro in excel

hi

I just create some macro in excel and i need some help to finish it...

So... i need a code to stop the macro at some point. For example:

If mystring = somethink then
*** Stop/break the opretaion ***
EndIf

I try with stop function and it does not work as i need it...

Thx

An

VB Code:

Exit Sub

will do

for quitting program

End

for exiting a subject

Exit Sub