====== Modify Variable Action ======

Modify Variable Action is a useful action that can alter rule variable values. Actions that works after this action uses altered values.

^Parameter Name^Description^
^Variable Name|The name of the variable we want to change|
^Find|Value we want to change|
^Replace|Value we want to use instead|

==== Use Cases ====

^Variable Value^Find^Replace^Result^
|SambaPOS|<empty>|Best|Best|
|SambaPOS|Samba|Best|BestPOS|
|SambaPOS|S(.*)S|Best|Best|
|SambaPOS|<empty|(S.*)POS|Samba|

On last two cases we used Regular Expressions. 
  * When Regex used as Find value it replaces variable with replace value if Find value successfully matches. 
  * When Regex used as Replace value it replaces variable with first regex group (the part in paranthesis) if regex matches.

==== Example ====

Suppose you are using ''NumberPad Value Entered'' rule to scan customer cards through magnetic card reader. Some card scanners sends mag card data between '';'' and ''?'' characters. As you know we can read entered number with ''NumberpadValue'' parameter so before using ''NumberpadValue'' parameter you might want to trim these characters. 

{{:en:actions:modifyvariable:modifyvariableaction1.jpg?700|}}

''[;|%](.*)\?'' regular expression trims starting '';'' or ''%'' char and ending ''?'' character. If we call this action before using NumberpadValue in ''Numberpad Value Entered'' rule we'll read trimmed value.

{{:en:actions:modifyvariable:modifyvariableaction2.jpg?700|}}