calculate the number of characters in a variable

Question

I am trying to calculate the length of an output from a set. It is very important to me I try to calculate this with out enable delayaedexpansion just raw batch.

@echo off
cls
set aaa=asdf
  for %%a in ("%aaa%") do (
  set /a bbb=%%~za + 0 
  echo %bbb%
)

If I do not add the +0, it keeps returning missing operand. If I put the +0 on , it keeps returning ECHO is off. This is not the first time I have tried to do a numerical echo. I am confused as to why letters will echo just fine but numbers will not.

Answer 1

I think that %%~z only works for files, not for variables. So, write the contents of the variable to a file, and get the file size.

What about this:

@echo off
set aaa=asdf

:: Write variable to file
set tmpfile=%TEMP%\%RANDOM%
echo %aaa%> %tmpfile%

:: Determine filesize, subtract 2 bytes for newline
for /F "usebackq" %%a in ('%tmpfile%') do set /a size=%%~za - 2

del %tmpfile%

echo Size: %size%