Set Extension

Author: Aaron's rod (talk, contrib)

Description

Simple function to set / change file extension.

Usage

  Push ".exe"
  Push "C:\some dir\some file.txt"
  Call SetExtension
  Pop $R0       ; $R0 = "C:\some dir\some file.exe"

Function

Function SetExtension
  Exch $R0
  Exch
  Exch $R1
  Push $R2
  Push $R3
 
  StrCpy $R3 1
 
  trim_loop:
  StrCpy $R2 "$R0" 1 -$R3
  StrCmp $R2 "\" trim_add 0
  StrCmp $R2 "" trim_add 0
 
  StrCmp $R2 "." 0 trim_cn
  StrCpy $R2 "$R0" "" -$R3
  StrCmp "$R2" "$R1" trim_ok 0
  StrCpy $R2 "$R0" -$R3
  StrCpy $R0 "$R2$R1"
  goto trim_ok
 
  trim_cn:
  IntOp $R3 $R3 + 1
  goto trim_loop
 
  trim_add:
  StrCpy $R0 "$R0$R1"
 
  trim_ok:
 
  Pop $R3
  Pop $R2
  Pop $R1
  Exch $R0
FunctionEnd