在批处理脚本中使用文本文件中的数据

Question

Batch contents:

FOR /F "tokens=1,*" %%i IN (list.txt) DO (
    cd "%%j"
    Echo %CD%
    pause
)

Execution run:

C:\Dwn>tmp1.bat

C:\Dwn>FOR /F "tokens=1,*" %i IN (list.txt) DO (
cd "%j"
 Echo C:\Dwn
 pause
)

C:\Dwn>(
cd "%APPDATA%\Microsoft\Windows\Start Menu\Programs\Administrative Tools"
 Echo C:\Dwn
 pause
)
The system cannot find the path specified.
C:\Dwn
Press any key to continue . . .

How come the system cannot find the path specified ? If I copy that cd command and execute it by itself it works fine.

Answer 1

It fails because the value of %%j contains %APPDATA%. The value of %APPDATA% will not get expanded when you expand %%j because environment variable expansion occurs before FOR variable expansion.

The fix is to use call cd "%%j" instead. The CALL will cause the command to go through an extra level of %VAR% expansion, which is exactly what you want.

You also have a problem in that you use echo %CD% within the same DO code block. It will echo the value of the current directory before your change because the value of %CD% is expanded when the entire FOR statement is parsed. You could fix this by using call echo %CD% , or by enabling delayed expansion with SETLOCAL EnableDelayedExpansion and using echo !CD! . But the simplest fix is to simply use cd ; the CD command without any arguments will print the current directory to the screen.