如何在不同的 .bat 文件中调用动态标签
How to call a dynamic label in different .bat file
如果我想从 bar.bat 调用 foo.bat 中的 :foo 我会这样做：
::foo.bat
echo.wont be executed
exit /b 1
:foo
echo foo from foo.bat
exit /b 0
和
::bar.bat
call :foo
exit /b %errorlevel%
:foo
foo.bat
echo.will also not be executed
但如果我不知道标签名称但将其作为参数传递，我就会陷入困境
::bar.bat
:: calling a dynamic label is no problem
call :%~1
exit /b %errorlevel%
::don't know how to "catch-all" or set context of "current-label"
:%~1
foo.bat
foo.bat（中学）：
@echo off
echo this is foo.bat
REM check, if the label is defined in this script:
findstr /xi "%~1" %~f0 >nul 2>&1 || goto :error
goto %~1
:foo
echo reached foo.bat, label :foo
exit /b 0
:error
echo wrong or missing label: "%~1"
exit /b 1
bar.bat（小学）
@echo off
echo this is bar.bat
call foo.bat :foo
echo back to bar.bat - %errorlevel%
call foo.bat :foe
echo back to bar.bat - %errorlevel%
call foo.bat
echo back to bar.bat - %errorlevel%
exit /b
您可以使用批量解析器技巧。
您无需在 foo.bat 中执行任何操作即可运行
::foo.bat
echo.wont be executed
exit /b 1
:func1
echo foo from foo.bat
exit /b 0
:unknown
echo Hello from %0 Func :unknown
exit /b
你只需要在 bar.bat 中添加你想在 foo.bat
中调用的任何标签
@echo off
::bar.bat
call :unknown
echo Back from Foo
call :func1
echo Back from Foo
exit /b %errorlevel%
:unknown
:func1
foo.bat
echo NEVER COMES BACK HERE
诀窍是在 bar.bat 中调用一个标签然后开始 foo.bat 而没有 调用它（仅 foo.bat）， foo.bat加载完毕，跳转到上次调用的标签。
正如 aschipfl 已经正确指出的那样，您不能拥有动态标签，但您可以动态调用当前标签，但您应该像 Stephan 那样在调用它之前检查它是否存在，但在第一批中。
所以这是 Stephans 和 jebs 批次的组合。
:: bar.bat
@echo off
REM check, if the label is defined in this script:
If "%~1" neq "" findstr /xi "%~1" %~f0 >nul 2>&1||goto :error&&Call :%~1
call :Func1
echo Back from Foo
call :func2
echo Back from Foo
exit /b %errorlevel%
:error
echo wrong or missing label: "%~1"
exit /b 1
:func1
:func2
foo.bat
echo NEVER COMES BACK HERE
:: foo.bat
@Goto :Eof
:func1
echo reached foo.bat, label :func1
exit /b 0
:func2
echo reached foo.bat, label :func2
exit /b 0
示例输出：
> bar
reached foo.bat, label :func1
Back from Foo
reached foo.bat, label :func2
Back from Foo
> bar fx
wrong or missing label: "fx"
在解析环境变量或参数引用之前，解析器会逐字搜索标签，因此您不能在标签中使用此类。
但是，在此我想提供一种允许使用动态标签的方法，虽然我不明白这样做的目的是什么，所以这更像是一个学术性的答案...
cmd的批处理文件解析器不缓存批处理文件，它是逐行读取并执行的，或者正确地说，它是单独读取并执行每个命令line/block。因此，我们可以利用它并让批处理文件在执行期间自行修改，前提是修改的部分超出了当前执行的代码部分。以下脚本实现了这一点：
@echo off
setlocal EnableExtensions DisableDelayedExpansion
rem // Check whether a label name has been delivered:
if "%~1"=="" (
echo ERROR: No label name specified! 1>&2
exit /B 1
)
rem /* Call sub-routine to replace the literal label string `:%~1`
rem within this batch file by the given dynamic label name: */
call :REPLACE_LINE "%~f0" ":%%%%~1" ":%~1" || (
rem /* In case the given label is `:REPLACE_TEXT`, display error
rem message, clean up temporary file and quit script: */
>&2 echo ERROR: Label ":%~1" is already defined!
2> nul del "%~f0.tmp"
exit /B 1
)
rem // Perform call of the sub-routine with the dynamic label name:
call :%~1
rem /* Call sub-routine to replace the given dynamic label name
rem within this batch file by the literal label string `:%~1`: */
call :REPLACE_LINE "%~f0" ":%~1" ":%%%%~1"
endlocal
exit /B
:REPLACE_LINE val_file_path val_line_LOLD val_line_LNEW
::This sub-routine searches a file for a certain line
::case-insensitively and replaces it by another line.
::ARGUMENTS:
:: val_file_path path to the file;
:: val_line_LOLD line to search for;
:: val_line_LNEW line to replace the found line;
setlocal DisableDelayedExpansion
rem // Store provided arguments:
set "FILE=%~1" & rem // (path of the file to replace lines)
set "LOLD=%~2" & rem // (line string to search for)
set "LNEW=%~3" & rem // (line string to replace the found line)
set "LLOC=%~0" & rem // (label of this sub-routine)
rem // Write output to temporary file:
> "%FILE%.tmp" (
rem /* Read the file line by line; precede each line by a
rem line number and `:`, so empty lines do not appear as
rem empty to `for /F`, as this would ignore them: */
for /F "delims=" %%L in ('findstr /N "^" "%FILE%"') do (
rem // Store current line with the line number prefix:
set "LINE=%%L"
setlocal EnableDelayedExpansion
rem // Check current line against search string:
if /I "!LINE:*:=!"=="!LOLD!" (
rem // Current line equals search string, so replace:
echo(!LNEW!
) else if /I not "!LNEW!"=="!LLOC!" (
rem // Current line is different, so keep it:
echo(!LINE:*:=!
) else (
rem /* Current line equals label of this sub-routine,
rem so terminate this and return with error: */
exit /B 1
)
endlocal
)
)
rem /* Searching and replacement finished, so move temporary file
rem onto original one, thus overwriting it: */
> nul move /Y "%FILE%.tmp" "%FILE%"
endlocal
exit /B
:%~1
::This is the sub-routine with the dynamic label.
::Note that it must be placed after all the other code!
echo Sub-routine.
exit /B
基本上，它首先用作为第一个命令行参数提供的字符串替换文字标签字符串（行）:%~1，然后它通过 call :%~1 调用该部分，最后，它恢复原始文字标签字符串。替换由子例程 :REPLACE_LINE.
管理
如果我想从 bar.bat 调用 foo.bat 中的 :foo 我会这样做：
::foo.bat
echo.wont be executed
exit /b 1
:foo
echo foo from foo.bat
exit /b 0
和
::bar.bat
call :foo
exit /b %errorlevel%
:foo
foo.bat
echo.will also not be executed
但如果我不知道标签名称但将其作为参数传递，我就会陷入困境
::bar.bat
:: calling a dynamic label is no problem
call :%~1
exit /b %errorlevel%
::don't know how to "catch-all" or set context of "current-label"
:%~1
foo.bat
foo.bat（中学）：
@echo off
echo this is foo.bat
REM check, if the label is defined in this script:
findstr /xi "%~1" %~f0 >nul 2>&1 || goto :error
goto %~1
:foo
echo reached foo.bat, label :foo
exit /b 0
:error
echo wrong or missing label: "%~1"
exit /b 1
bar.bat（小学）
@echo off
echo this is bar.bat
call foo.bat :foo
echo back to bar.bat - %errorlevel%
call foo.bat :foe
echo back to bar.bat - %errorlevel%
call foo.bat
echo back to bar.bat - %errorlevel%
exit /b
您可以使用批量解析器技巧。
您无需在 foo.bat 中执行任何操作即可运行
::foo.bat
echo.wont be executed
exit /b 1
:func1
echo foo from foo.bat
exit /b 0
:unknown
echo Hello from %0 Func :unknown
exit /b
你只需要在 bar.bat 中添加你想在 foo.bat
@echo off
::bar.bat
call :unknown
echo Back from Foo
call :func1
echo Back from Foo
exit /b %errorlevel%
:unknown
:func1
foo.bat
echo NEVER COMES BACK HERE
诀窍是在 bar.bat 中调用一个标签然后开始 foo.bat 而没有 调用它（仅 foo.bat）， foo.bat加载完毕，跳转到上次调用的标签。
正如 aschipfl 已经正确指出的那样，您不能拥有动态标签，但您可以动态调用当前标签，但您应该像 Stephan 那样在调用它之前检查它是否存在，但在第一批中。
所以这是 Stephans 和 jebs 批次的组合。
:: bar.bat
@echo off
REM check, if the label is defined in this script:
If "%~1" neq "" findstr /xi "%~1" %~f0 >nul 2>&1||goto :error&&Call :%~1
call :Func1
echo Back from Foo
call :func2
echo Back from Foo
exit /b %errorlevel%
:error
echo wrong or missing label: "%~1"
exit /b 1
:func1
:func2
foo.bat
echo NEVER COMES BACK HERE
:: foo.bat
@Goto :Eof
:func1
echo reached foo.bat, label :func1
exit /b 0
:func2
echo reached foo.bat, label :func2
exit /b 0
示例输出：
> bar
reached foo.bat, label :func1
Back from Foo
reached foo.bat, label :func2
Back from Foo
> bar fx
wrong or missing label: "fx"
在解析环境变量或参数引用之前，解析器会逐字搜索标签，因此您不能在标签中使用此类。
但是，在此我想提供一种允许使用动态标签的方法，虽然我不明白这样做的目的是什么，所以这更像是一个学术性的答案...
cmd的批处理文件解析器不缓存批处理文件，它是逐行读取并执行的，或者正确地说，它是单独读取并执行每个命令line/block。因此，我们可以利用它并让批处理文件在执行期间自行修改，前提是修改的部分超出了当前执行的代码部分。以下脚本实现了这一点：
@echo off
setlocal EnableExtensions DisableDelayedExpansion
rem // Check whether a label name has been delivered:
if "%~1"=="" (
echo ERROR: No label name specified! 1>&2
exit /B 1
)
rem /* Call sub-routine to replace the literal label string `:%~1`
rem within this batch file by the given dynamic label name: */
call :REPLACE_LINE "%~f0" ":%%%%~1" ":%~1" || (
rem /* In case the given label is `:REPLACE_TEXT`, display error
rem message, clean up temporary file and quit script: */
>&2 echo ERROR: Label ":%~1" is already defined!
2> nul del "%~f0.tmp"
exit /B 1
)
rem // Perform call of the sub-routine with the dynamic label name:
call :%~1
rem /* Call sub-routine to replace the given dynamic label name
rem within this batch file by the literal label string `:%~1`: */
call :REPLACE_LINE "%~f0" ":%~1" ":%%%%~1"
endlocal
exit /B
:REPLACE_LINE val_file_path val_line_LOLD val_line_LNEW
::This sub-routine searches a file for a certain line
::case-insensitively and replaces it by another line.
::ARGUMENTS:
:: val_file_path path to the file;
:: val_line_LOLD line to search for;
:: val_line_LNEW line to replace the found line;
setlocal DisableDelayedExpansion
rem // Store provided arguments:
set "FILE=%~1" & rem // (path of the file to replace lines)
set "LOLD=%~2" & rem // (line string to search for)
set "LNEW=%~3" & rem // (line string to replace the found line)
set "LLOC=%~0" & rem // (label of this sub-routine)
rem // Write output to temporary file:
> "%FILE%.tmp" (
rem /* Read the file line by line; precede each line by a
rem line number and `:`, so empty lines do not appear as
rem empty to `for /F`, as this would ignore them: */
for /F "delims=" %%L in ('findstr /N "^" "%FILE%"') do (
rem // Store current line with the line number prefix:
set "LINE=%%L"
setlocal EnableDelayedExpansion
rem // Check current line against search string:
if /I "!LINE:*:=!"=="!LOLD!" (
rem // Current line equals search string, so replace:
echo(!LNEW!
) else if /I not "!LNEW!"=="!LLOC!" (
rem // Current line is different, so keep it:
echo(!LINE:*:=!
) else (
rem /* Current line equals label of this sub-routine,
rem so terminate this and return with error: */
exit /B 1
)
endlocal
)
)
rem /* Searching and replacement finished, so move temporary file
rem onto original one, thus overwriting it: */
> nul move /Y "%FILE%.tmp" "%FILE%"
endlocal
exit /B
:%~1
::This is the sub-routine with the dynamic label.
::Note that it must be placed after all the other code!
echo Sub-routine.
exit /B
基本上，它首先用作为第一个命令行参数提供的字符串替换文字标签字符串（行）:%~1，然后它通过 call :%~1 调用该部分，最后，它恢复原始文字标签字符串。替换由子例程 :REPLACE_LINE.