IndexOf & RIndexOf: Find index of character in string
From NSIS Wiki
Jump to navigationJump to search
| Author: Afrow UK (talk, contrib) |
Description
These two functions find the index of a character in a string from left (IndexOf) or from the right (RIndexOf). For the default behaviour of StrCpy, IndexOf returns the character index as zero-based, whereas RIndexOf does not (starts at 1 from the end).
Written for cowwoc in this forum topic.
Usage
${IndexOf} $R0 "blah" "a" ; $R0 = 2 ${RIndexOf} $R0 "blah" "b" ; $R0 = 4
The Functions
Function IndexOf Exch $R0 Exch Exch $R1 Push $R2 Push $R3 StrCpy $R3 $R0 StrCpy $R0 -1 IntOp $R0 $R0 + 1 StrCpy $R2 $R3 1 $R0 StrCmp $R2 "" +2 StrCmp $R2 $R1 +2 -3 StrCpy $R0 -1 Pop $R3 Pop $R2 Pop $R1 Exch $R0 FunctionEnd !macro IndexOf Var Str Char Push "${Char}" Push "${Str}" Call IndexOf Pop "${Var}" !macroend !define IndexOf "!insertmacro IndexOf" Function RIndexOf Exch $R0 Exch Exch $R1 Push $R2 Push $R3 StrCpy $R3 $R0 StrCpy $R0 0 IntOp $R0 $R0 + 1 StrCpy $R2 $R3 1 -$R0 StrCmp $R2 "" +2 StrCmp $R2 $R1 +2 -3 StrCpy $R0 -1 Pop $R3 Pop $R2 Pop $R1 Exch $R0 FunctionEnd !macro RIndexOf Var Str Char Push "${Char}" Push "${Str}" Call RIndexOf Pop "${Var}" !macroend !define RIndexOf "!insertmacro RIndexOf"
-Stu
