Windows CMD - 在 for 循环中设置不起作用

Question

我想编写批处理文件，它将遍历包含备份目录的所有目录并删除其中超过 X 天的文件。 在我想运行我的脚本的计算机上没有“forfile”命令。 没有 PowerShell，所以 CMD 或 VBScripts 似乎是完成这项任务的唯一方法。

目前我的“set”语句有问题 - 当我调用 %checkpath% 时，我似乎没有收到预期的文件夹。

rem we will memorize current directory
pushd %cd%
set folder="C:\Documents and Settings\myname\Desktop"
cd %folder%
rem loop only folders with five chars within their names (unfortunately on less also
for /D %%g in (?????) DO (
    set checkpath="%cd%\%%g\backup"
    if exist %checkpath% (
        for %%a in ('%%g\backup\*.*') do (
        set FileDate=%%~ta
        set FileDate=%%FileDate:~0,10%%
        rem here I want to compare file modification data with current date
        )
    )
popd
pause

Answer 1

您需要使用延迟扩展来读取您在for 循环中设置的变量。

试试这个

setlocal enabledelayedexpansion
rem we will memorize current directory
pushd %cd%
set folder="C:\Documents and Settings\myname\Desktop"
cd %folder%
rem loop only folders with five chars within their names (unfortunately on less also
for /D %%g in (?????) DO (
    set checkpath="%cd%\%%g\backup"
    if exist !checkpath! (
        for %%a in ('%%g\backup\*.*') do (
        set FileDate=%%~ta
        set FileDate=!%FileDate:~0,10%!
        rem here I want to compare file modification data with current date
        )
    )
popd
pause

将您创建的变量上的% 替换为! 将指示它改为使用延迟扩展。

Answer 2

巴厘岛的回答有一个小错误。第二个set filedate 不正确，否则他很好，但如果您没有启用延迟扩展，则可能无法正常工作。我修正了他的错误并向您展示了如何确保启用延迟扩展。我还做了一些其他更改：

::This command will ensure that the delayed expansion, i.e. the "!"s below, 
::  will work.  Unfortunately, it also means you loose the results of any
::  "set" commands as soon as you execute the "endlocal" below.
setlocal ENABLEDELAYEDEXPANSION

::you might want
::set "folder=%USERPROFILE%\Desktop"
set "folder=C:\Documents and Settings\myname\Desktop"

rem we will memorize current directory
::If you ran this code with the current directory set to a directory on
::a drive other than C:, your previous code would not have worked to
:: change to your desired target directory.  this slight change fixes that.
pushd "%folder%"

rem loop only folders with five chars within their names - unfortunately on less also
::Use capitals for your loop variables.  The var names are case sensitive, and 
::using capitals ensures there is no confusion between the var names and ~modifiers
for /D %%G in ( ????? ) DO (
    set checkpath="%CD%\%%G\backup"
    if exist !checkpath! (
        for %%A in ('%%G\backup\*.*') do (
            set FileDate=%%~tA
            set FileDate=!FileDate:~0,10!
            rem here I want to compare file modification data with current date
        )
)
popd
endlocal
pause

但是，如果你这样写，你就不需要“setlocal”或延迟扩展：

::you might want
::set "folder=%USERPROFILE%\Desktop"
set "folder=C:\Documents and Settings\myname\Desktop"

rem we will memorize current directory
::If you ran this code with the current directory set to a directory on
::a drive other than C:, your previous code would not have worked to
:: change to your desired target directory.  this slight change fixes that.
pushd "%folder%"

rem loop only folders with five chars within their names - unfortunately on less also
for /D %%G in ( ????? ) DO (
    if exist "%%~G\backup" (
        for %%A in ('%%~G\backup\*.*') do (
            for /F "usebackq" %%T in ( '%%~tA' ) do (
                echo File date is %%T, todays date is %DATE%
            )
        )
)
popd
pause