使用EnableDelayedExpansion时，修改变量的语法是正确的 [英] Correct syntax for variable modifiers when using EnableDelayedExpansion

问题描述

我希望能够做到％〜p只能看到文件的路径。但是我不能在循环中使用正确的语法（使用EnableDelayedExpansion）

这是我的代码：

<$






$ b $ set

setlocal EnableDelayedExpansion
for（f）/ f %% F in（'dir / a：-d / s / b / r％dir1％'）do（
set file_path = %% F
setfile_name = %%〜nF
setnew_path =！file_path：％dir1％=％dir2％！
setnew_path =！new_path ：！file_name！=％empty％//这个命令有问题
echo！new_path！
）
endlocal

有什么办法可以做到这一点？ 解决方案

并替换文件路径。



$ set $ set $ set $ set b

$ dir1 =％TMP％\opt
setdir2 = c：\opt

pushd％dir1％&& （'dir / a：-d / b / r / s'）do（
setfile_path = %%〜dpF
setnew_path =！file_path：％ dir1％=％dir2％！
echo！new_path！
）& popd

endlocal
exit / b 0

说明 h3>

主要的变化是使用变量的〜dp 修饰符，它使得它只获得完整的文件路径没有文件名。

您使用的dir1替换是正确的，这是您的文件名替换是不好的。通过使用〜dp 修饰符，我们可以完全跳过文件名替换部分。
$ b 循环开始设置工作目录

<设置工作目录为 dir1 $ $ $ $ $ $ $ $ <$> b $ b

循环访问该目录中的所有文件和子目录。


对于每个文件，只需获取文件路径 C：\Path\opt \sub 不是 C：\path\opt\sub\file.ext

将 C：\path\opt 替换为 C：\opt

显示结果

popd 会将工作目录恢复到 pushd 。

以下是中所有变量修饰符的列表/？ help text。

 另外，FOR变量引用已经得到增强。 
您现在可以使用以下可选语法：
 
％〜I  - 展开％我删除任何周围的引号（）
％〜fI  - 将％I扩展为完全限定路径名
％〜dI  - 仅将％I扩展为驱动器号
％〜pI  - 将％I扩展为仅路径
％〜nI  - 将％I扩展为文件名
％〜xI  - 仅将％I扩展为文件扩展名
％〜sI  - 扩展路径仅包含短名称
％〜aI  - 将％I扩展为文件的文件属性
％ 〜tI  - 将％I扩展为文件的日期/时间
％〜zI  - 将％I扩展为文件大小
％〜$ PATH：I  - 搜索PATH 
环境中列出的目录变量并将％I扩展到第一个找到的
全限定名称
如果环境变量名称不是
定义的或者
搜索没有找到该文件，那么这个修饰符扩展到
空字符串
 
修饰符可以合并得到复合结果：
 
％〜dpI  - 将％I扩展为驱动器号和路径
％〜nxI  - 扩展％I仅指定文件名和扩展名
％〜fsI  - 将％I扩展为仅包含短名称的完整路径名
％〜dp $ PATH：I  - 搜索PATH $ b中列出的目录$ b环境变量为％I，并展开到
驱动器号和找到的第一个路径。 
％〜ftzaI  - 将％I扩展为一个DIR，如输出行
 
在上面的例子中，％I和PATH可以被其他有效的
值替换。 ％〜语法由一个有效的FOR变量名称终止。 
采用大写字母变量名称（例如％I）使其更具可读性，
可避免与大小写不敏感的修饰符混淆。 
  

I want to be able to do %~p to only see the path of the file. But I cant get the correct syntax when using it in a loop (With EnableDelayedExpansion)

Here's my code:

@echo off
set "dir1=%TMP%\opt"
set "dir2=c:\opt"
set "empty="

setlocal EnableDelayedExpansion
for /f %%F in ('dir  /a:-d /s /b /r "%dir1%"') do (
  set "file_path=%%F"
  set "file_name=%%~nF"
  set "new_path=!file_path:%dir1%=%dir2%!"
  set "new_path=!new_path:!file_name!=%empty%" //This command is problematic
  echo !new_path!
)
endlocal

Any way for me to do this?

解决方案

Here is how to get and replace just the file path.

@echo off
setlocal EnableDelayedExpansion

set "dir1=%TMP%\opt"
set "dir2=c:\opt"

pushd "%dir1%" && for /f %%F in ('dir /a:-d /b /r /s') do (
    set "file_path=%%~dpF"
    set "new_path=!file_path:%dir1%=%dir2%!"
    echo !new_path!
) & popd

endlocal
exit /b 0

Explanation

The main change is the use of the ~dp modifiers for the variable which causes it to just get the full file path without the file name.

Your usage of the dir1 replacement was correct, it was your file name replacement that was bad. By using the ~dp modifier we can skip the file name replacement part completely.

The pushd is only called once before the for loop begins to set the working directory.

Walkthrough:

• Set the working directory to dir1
• Loop through all the files in that directory and subdirectories.
• For each file get just the file path C:\Path\opt\sub not C:\path\opt\sub\file.ext
• Replace the C:\path\opt with C:\opt
• Display the result.
• popd will restore the working directory to what it was before the pushd.

Here is a list of all the variable modifiers from the for /? help text.

In addition, substitution of FOR variable references has been enhanced.
You can now use the following optional syntax:

%~I         - expands %I removing any surrounding quotes (")
%~fI        - expands %I to a fully qualified path name
%~dI        - expands %I to a drive letter only
%~pI        - expands %I to a path only
%~nI        - expands %I to a file name only
%~xI        - expands %I to a file extension only
%~sI        - expanded path contains short names only
%~aI        - expands %I to file attributes of file
%~tI        - expands %I to date/time of file
%~zI        - expands %I to size of file
%~$PATH:I   - searches the directories listed in the PATH
               environment variable and expands %I to the
               fully qualified name of the first one found.
               If the environment variable name is not
               defined or the file is not found by the
               search, then this modifier expands to the
               empty string

The modifiers can be combined to get compound results:

%~dpI       - expands %I to a drive letter and path only
%~nxI       - expands %I to a file name and extension only
%~fsI       - expands %I to a full path name with short names only
%~dp$PATH:I - searches the directories listed in the PATH
               environment variable for %I and expands to the
               drive letter and path of the first one found.
%~ftzaI     - expands %I to a DIR like output line

In the above examples %I and PATH can be replaced by other valid
values.  The %~ syntax is terminated by a valid FOR variable name.
Picking upper case variable names like %I makes it more readable and
avoids confusion with the modifiers, which are not case sensitive.

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