How to split string without for loop in batch file

You can try this . If its fixed that numbers to left of the colon will be always 2 & to the right will be 3. Then following code should work assuming your str has the value.

set "str=45:abc"
echo %str%
set var1=%str:~0,2%
set var2=%str:~3,3%
echo %var1% %var2%

Keep me posted. :)

It seems pointless to avoid using a FOR loop, but it does make the problem interesting.

As jeb has pointed out, getting the trailing part is easy using !str:*:=!.

The tricky bit is the leading part. Here is an alternative to jeb's solution.

You can insert a linefeed into a variable in place of the : using the following syntax

setlocal enableDelayedExpansion
set "str=45:abc"
echo !str::=^

!

--OUTPUT--

45
abc

The empty line above the last ! is critical.

I'm not sure why, but when the output of the above is piped to a command, only the first line is preserved. So the output can be piped to a FINDSTR that matches any line, and that result directed to a file that can then be read into a variable using SET /P

Here is a complete solution:

@echo off
setlocal enableDelayedExpansion
set "str=45:abc"
echo(!str::=^

!|findstr "^" >test.tmp
<test.tmp set /p "var1="
del test.tmp
set "var2=!str:*:=!"
echo var1=!var1!  var2=!var2!

Update

I believe I've mostly figured out why the 2nd line is stripped from the output :)

It has to do with how pipes are handled by Windows cmd.exe with each side being processed by a new CMD.EXE thread. See Why does delayed expansion fail when inside a piped block of code? for a related question with a great answer from jeb.

Just looking at the left side of the piped command, I believe it is parsed (in memory) into a statement that looks like

C:\Windows\system32\cmd.exe /S /D /c" echo {delayedExpansionExpression}"

I use {delayedExpansionExpression} to represent the multi-line search and replace expansion that has not yet occurred.

Next, I think the variable expression is actually expanded and the line is broken in two by the search and replace:

C:\Windows\system32\cmd.exe /S /D /c" echo 43
abc"

Only then is the command executed, and by normal cmd.exe rules, the command ends at the linefeed. The quoted command string is missing the end quote, but the parser doesn't care about that.

The part I am still puzzled by is what happens to the abc"? I would have thought that an attempt would be made to execute it, resulting in an error message like 'abc"' is not recognized as an internal or external command, operable program or batch file. But instead it appears to simply get lost in the ether. note - jeb's 3rd comment explains why :)

Safe version without FOR

My original solution will not work with a string like "&|<". Here is a variation without FOR that should work with nearly any string, except for string length limits and trailing control chars will be stripped from leading part.

@echo off
setlocal enableDelayedExpansion
set "str=this & that:cats & dogs"
set ^"str2=!str::=^

!^"
cmd /v:on /c echo ^^!str2^^!|findstr /v "$" >test.tmp
<test.tmp set /p "var1="
del test.tmp
set "var2=!str:*:=!"
echo var1=!var1!  var2=!var2!

I delay the expansion until the new CMD thread, and I use a quirk of FINDSTR regex that $ only matches lines that end with <cr>. The first line doesn't have it and the second does. The /v option inverts the result.