How to Modify [System : Variable]

[System: Variable]
LocVar : "This is the default value"
[Variable: LocVar]
Type : String

[#Menu : Gateway of Tally]
Item : BLANK
Key Item : Brokerwise Receivables : R : Display : Test
[Report : Test]
Form : Test
[Form: Test]
Part: Test
[Part: Test]
Line: L1, L2, L3, L4
[Line: L1]
Field: Name Field
Local: Field: Name Field : Set as : @@CmpMailName
[Line: L2]
Field: Name Field
Local: Field: Name Field : Set as : ##LocVar
[Line: L3]
Field: LT
[Field: LT]
Use : ShortNameField
Set As : "Indian" ;@@CmpMailName
Variable : LocVar
Modifies : LocVar
[Line: L4]
Field: Name Field
Local: Field: Name Field : Set as : ##LocVar
;;-------------------------- End

Unable to Modify / Assign value to Variable : LocVar, What is correct way.
According to the code Last value of LocVar should be "Indian". But not getting modified. What is mistake ?

 

Thanks for the reply, But Sir, I want the value of Variable LocVar has to change / assign, for further usage

 

No Sir, Not Working.
My Requirement : Want to "modify / change / assign" "System Variable(eg. LocVar)" with a "Field Value" in a "Part".
And will be using this Changed System Variable to Filter a Collection.

 

change it through button
where u call a report n modify in field level

 

This code is in "Print Receipt". Any way by Function ?

 

it can be through function or report

 

Thank You Sirji, First I created A Bottom in "Voucher Entry/Alter Mode" to Print the Voucher. With this I set the value of System Variable in a Function then call to Print Report. Once again thanks