CMD DOS BATCH – Example of Variable passed to subroutine-Function as reference

CMD DOS BATCH – Example of Variable passed to subroutine-Function  as reference

Quick example of how a variable passed to a DOS subroutine (or function) is by reference.

Steps:

1.       Begin with original value “MyOriginalString”

2.       Pass variable with original string

3.       Subroutine appends the value “_MyAppendedValue”

4.       Echo out the revised variable in the calling function echos as “MyOriginalString_MyAppendedValue”

Test.cmd:

@echo off cls setlocal enabledelayedexpansion set myVar=MyOriginalString echo myVar 1 =!myVar! call :mysub myVar echo myVar 2 =!myVar! goto:eof :mysub setlocal enabledelayedexpansion echo local is set here echo The NAME of the passed argument is:%1 echo The VALUE of the passed argument is:!%1! set "holdValue=!%1!" echo local is ended here endlocal & set "%1=%holdValue%_MyAppendedValue" goto:eof

Output example:

myVar 1 =MyOriginalString local is set here The NAME of the passed argument is:myVar The VALUE of the passed argument is:MyOriginalString local is ended here myVar 2 =MyOriginalString_MyAppendedValue