CMD试图在循环中设置变量(CMD trying to set variable in a loop)

 我正在使用windows'cmd并尝试在循环中设置变量。 这是我的代码： 
 
for /d %%a in ("F:\backup*") do set folder=%%a
ECHO %folder%
PAUSE
 
 我想在驱动器F上查找名称以“backup”开头的文件夹，并将该文件夹的名称保存到％folder％variable。 因此，例如，如果文件夹将被称为“备份2017-01-18”，我希望保存到var。 
 
 相反它似乎没有设置任何东西，因为ECHO只打印“ECHO开启”。 for循环是正确的，文件夹也在那里（我已经将这段代码用于robocopy的其他批处理）。 
 
 理论上我可以将所有代码放在FOR循环中并使用%% a而不是％文件夹％var，但这似乎是一个hacky解决方案。 
 
 到目前为止，我发现的所有解决方案都指向使用EnableDelayedExpansion。 我修改了代码以使用它： 
 
Setlocal EnableDelayedExpansion
for /d %%a in ("F:\backup*") do set folder=%%a
ECHO !folder!
PAUSE
 
 但现在ECHO打印“！文件夹！” 好像它不会检测到变量。 如果我恢复到ECHO％文件夹％I，我再次得知“ECHO已开启”。 
 
 编辑：我在这里发现了这个问题。 我还在备份文件夹上运行另一个批处理文件。 事实证明，ROBOCOPY（我在该批次中使用的）默认情况下将封闭文件夹设置为隐藏，系统和只读（即使复制的文件未被隐藏或系统为o_0）。 当我删除目录上的HSR属性时，此处发布的代码开始正常工作（初始版本）。 

I'm working with windows' cmd and trying to set a variable in a loop. Here's the code I have:
 
for /d %%a in ("F:\backup*") do set folder=%%a
ECHO %folder%
PAUSE
 
I want to look for a folder with name starting with "backup" on drive F and save that folder's name to %folder% variable. So for example if the folder would be called "backup 2017-01-18" I'd like that saved to a var.
 
Instead it doesn't seem to set anything as the ECHO just prints that "ECHO is on". The for loop is correct and the folder is there as well (I'm already using that piece of code for other batch with robocopy).
 
I could theoretically put all my code inside the FOR loop and use %%a instead of the %folder% var but that seems like a hacky solution.
 
All the solutions I found so far pointed to using EnableDelayedExpansion. I modified the code to use it like that:
 
Setlocal EnableDelayedExpansion
for /d %%a in ("F:\backup*") do set folder=%%a
ECHO !folder!
PAUSE
 
But now ECHO prints "!folder!" as if it would not detect the variable. If I revert to ECHO %folder% I once again learn that "ECHO is on".
 
EDIT: I found the issue here. I was also running another batch file on the backup folder. It turns out that ROBOCOPY (which I used in that batch) is setting the enclosing folder to hidden, system and readonly by default (even if copied files are not hidden or system o_0). When I removed HSR attributes on the directory the code posted here started working fine (the initial version).

原文：https://stackoverflow.com/questions/41720393