批处理set变量失败，这是因为什么

hentai87

1. @echo off
   
2. pushd "%~dp0"
   
3. 
   
4. for /f "delims=:" %%a in ('findstr /n msmg设置 ..\set.txt') do set n=%%a
   
5.         for /f "skip=%n% delims=" %%b in (..\set.txt) do (
   
6. set dism=%%b\Bin\x64\DISM10\dism.exe
   
7. echo %dism%
   
8. )
   
9. 
   
10. pause

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结果
ECHO is off.
Press any key to continue . . .

但是这样就成功了
set var=我是值
echo %var%

是无法set %%b吗

smss

1. 加延迟变量试试

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hentai87

回复 2# smss


    setlocal EnableDelayedExpansion

D:\lopatkin\Package_Remover\Remove-package>for /F "delims=:" %a in ('findstr /n msmg设置 ..\set.txt') do set n=%a

D:\lopatkin\Package_Remover\Remove-package>set n=2

D:\lopatkin\Package_Remover\Remove-package>for /F "skip=2 delims=" %b in (..\set.txt) do (
set dism=%b\Bin\x64\DISM10\dism.exe
echo
)

D:\lopatkin\Package_Remover\Remove-package>(
set dism=D:\ZT\ToolKit_v9.9\Bin\x64\DISM10\dism.exe
echo
)
ECHO is on.


还是这样

flashercs

1. @echo off
   
2. pushd "%~dp0"
   
3. 
   
4. for /f "delims=:" %%a in ('findstr /n msmg设置 ..\set.txt') do set n=%%a
   
5.         for /f "skip=%n% delims=" %%b in (..\set.txt) do (
   
6. set dism=%%b\Bin\x64\DISM10\dism.exe
   
7. )
   
8. echo %dism%
   
9. pause

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cmd命令行的括号()中的所有语句等同于一行代码,而cmd执行每一行语句前要给该行代码的所有变量进行预赋值,此时%dism%还是空值,所以echo %dism%等同于echo 空白.

Batcher

回复 1# hentai87

1. @echo off
   
2. setlocal enabledelayedexpansion
   
3. pushd "%~dp0"
   
4. for /f "delims=:" %%a in ('findstr /n msmg设置 ..\set.txt') do (
   
5.     call :GetDISM %%a
   
6. )
   
7. pause
   
8. goto :eof
   
9. 
   
10. :GetDISM
    
11. for /f "skip=%1 delims=" %%b in (..\set.txt) do (
    
12.     set "dism=%%b\Bin\x64\DISM10\dism.exe"
    
13.     echo,!dism!
    
14. )

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