ECHO没有显示变量，即使它们出现在SET - Windows批处理文件中

Question

In some code I'm working on, I need to connect to a terminal, which requires a terminal's IP address. Some of the code is here:

FOR /F "Tokens=1" %%A IN (%IPLIST%) DO (
NET USE //%%A /user:name password
SET TERMINAL=%%A
ECHO %TERMINAL%
)

However, after doing this, Echo responds with:

ECHO is off

As a test, I simply added SET after the ECHO %TERMINAL% Line, and according to it:

TERMINAL=10.123.45.6

So, my dilemma is that, according to SET, TERMINAL does indeed have a value, but ECHO doesn't agree.

The reason this is so important is because I cannot tell if the value is correct for future use in the rest of the code, where I implement it to enact different batches in a remote system.

Any help would be much appreciated!

Answer 1

I belive the reason is that FOR is evaluated as a single command and the environment variables are expanded before execution, so in your case it will be run like this:

FOR /F "Tokens=1" %A IN (<%IPLIST% value>) DO (
NET USE //%A /user:name password
SET TERMINAL=%A
ECHO <%TERMINAL% value>
)

Since %TERMINAL% didn't exist before FOR , it'll be expanded to an empty string, hence the observed behaviour.

Try running the script with @echo on , it helps understand what's going on.

UPDATE

You might be able to get the behaviour you want with Setlocal EnableDelayedExpansion , see this link for more details.