How to convert the value of %USERNAME% to lowercase within a Windows batch script?

Question

I\'m automating some source control software functionality using a dot bat script but given that our svn repos are hosted in a *NIX box, I\'m facing the eternal case problem

Answer 1

:: UPcase.bat ==> Store in environment variable _UPcase_ the upper case of %1
:: -> Use quotes "" when the first argument has blanks or special characteres
::
:: Adapted from -> http://www.netikka.net/tsneti/info/tscmd039.htm
::
:: Note that the substitution method is case insensitive, which means that
:: while working for this application, it is not useful for all character
:: substitution tasks.
::
:: More concisely, one can capitalize (if you pardon the pun) on the fact
:: that in for and the substitution lower and upper case source are
:: equivalent.
@echo off

:: %~1 -> removes quotes from the first command line argument
:: http://steve-jansen.github.io/guides/windows-batch-scripting/part-2-variables.html
@echo off
::setlocal EnableExtensions
    :: echo %_UPcase_%
    call :ToUpcaseWithFor "%~1" _UPcase_
    :: echo %_UPcase_% _doit_1_
::endlocal & goto :EOF
goto :EOF
::
:: ======================
:ToUpcaseWithFor
setlocal EnableExtensions EnableDelayedExpansion
  set var_=%~1
  for %%c in (A B C D E F G H I J K L M N O P Q R S T U V W X Y Z) do (
    set var_=!var_:%%c=%%c!
  )
endlocal & set %2=%var_%& goto :EOF

:EOF
:: UPcase.bat ==> EOF

Answer 2

In my batch file I'm doing a comparsion between %USERNAME% and a CSV file.

The program would not work if user was logged in UperCase username.

Ex:
Login : GB2NOGU // Won't work
Login : gb2nogu // Works

Here I could solve my problem doing a insensitive comparison.

if /i %USERNAME%==gb2nogu (
     // Code here
)

The parameter /i tells the cmd to do a insensitive case comparison, so it'll ignore the difference between lowercase and uppercase letters.

Answer 3

This is the same answer /by @It Wasn't Me here

---

For a predictive character set, this substring Set !var:A=a! works, and only working with predefined substring in bat/cmd.

For this type of task, why not get a little help with c#, which can make it possible to work with unconventional accents and consonants è, È, ä, Ä, ñ, Ñ, ç, Ç etc.

Where the bat/cmd will generate c# code, it will be compiled and executed at run time ....

Which solves possible user inputs, in which the sequence comes with accents and the vowels/consonants are different from the conventional ones [a-z] and/or [A_Z]

---

@echo off & setlocal EnableDelayedExpansion 

cd /d "%~dp0" && title <nul && title ...\%~dpnx0 /// !time:~0,8! !date!

if exist "%tmp%\ToUpLower.cs" 2>nul >nul del /q /f "%tmp%\ToUpLower.cs" 
set "_where=%__appdir__%where.exe" && set "_csc=%windir%\Microsoft.NET"
>"%temp%\ToUpLower.cs"  ( 
echo= using System; namespace SUQ1522019 ^{class Program ^{static void Main(string[] args^) ^{
echo= if (args.Length==2 ^&^& args[0].ToLower(^)=="-l"^) ^{Console.WriteLine(args[1].ToLower(^)^);^} 
echo= if (args.Length==2 ^&^& args[0].ToLower(^)=="-u"^) ^{Console.WriteLine(args[1].ToUpper(^)^);^}^}^}^}
)

set "_arg=/t:exe /out:"%tmp%\ToUpLower.exe" "%tmp%\ToUpLower.cs" /platform:anycpu "
for /f tokens^=* %%i in ('!_where! /r "!_csc!" "csc.exe"^|findstr /lic:"k\v2\." 
')do "%%~i" !_arg! /unsafe+ /w:0 /o /nologo

for /f tokens^=* %%U in ('"%tmp%\ToUpLower.exe" -u %USERNAME%')do set "_up_case=%%U"
for /f tokens^=* %%l in ('"%tmp%\ToUpLower.exe" -l %USERNAME%')do set "_low_case=%%l"

echo/  Your username upcase is: !_up_case!
echo/ Your username lowcase is: !_low_case!

echo/ >nul 2>nul copy "%tmp%\ToUpLower.exe" "." 
del /q /f "%tmp%\ToUpLower.*" >nul 2>nul && endlocal & goto :EOF

---

• Outputs for %USERNAME%

  ---

 Your username upcase is: USERNAME
Your username lowcase is: username

---

The ToUpLower.cs c# code with no escaping:

---

 using System; namespace SUQ1522019 {class Program {static void Main(string[] args) {
 if (args.Length==2 && args[0].ToLower()=="-l") {Console.WriteLine(args[1].ToLower());} 
 if (args.Length==2 && args[0].ToLower()=="-u") {Console.WriteLine(args[1].ToUpper());}}}}

---

The ToUpLower.cs c# code with no escaping and indented:

---

using System
namespace SUQ1522019 
{
   class Program 
   {
      static void Main(string[] args)
      {
         if (args.Length==2 && args[0].ToLower()=="-l") 
         {
            Console.WriteLine(args[1].ToLower());
         } 

         if (args.Length==2 && args[0].ToLower()=="-u") 
         {
            Console.WriteLine(args[1].ToUpper());
         }
      }
   }
}

---

• This c# code was compiled/tested on csc.exe versions:

c:\Windows\Microsoft.NET\Framework\v2.0.50727\csc.exe
c:\Windows\Microsoft.NET\Framework\v3.5\csc.exe
c:\Windows\Microsoft.NET\Framework\v4.0.30319\csc.exe
c:\Windows\Microsoft.NET\Framework64\v2.0.50727\csc.exe
c:\Windows\Microsoft.NET\Framework64\v3.5\csc.exe
c:\Windows\Microsoft.NET\Framework64\v4.0.30319\csc.exe

---

• This is the command line used to compile the c# code:

  ---

c:\Windows\Microsoft.NET\Framework\v2.0.50727\csc.exe /t:exe /out:"%tmp%\ToUpLower.exe" "%tmp%\ToUpLower.cs" /platform:anycpu /unsafe+ /w:0 /o /nologo 

---

• ToUpLower.exe usage UPPER to -> lower

  ---

ToUpLower.exe -l STRING 

:: or ..

ToUpLower.exe -L STRING

---

• ToUpLower.exe usage lower to -> UPPER

---

ToUpLower.exe -u string

:: or ..

ToUpLower.exe -U string

---

To keep ToUpLower.exe, remove echo/ from copy command:

---

echo/ >nul 2>nul copy "%tmp%\ToUpLower.exe" "." 

This command line will copy ToUpLower.exe from %temp% to same the same folder where your bat is running.

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Programming Guide C#:

• Args

• ToLower

• ToUpper

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_{Sorry my limited English}