文件重定向在Windows和％ERRORLEVEL％ [英] File redirection in Windows and %errorlevel%

问题描述

假设我们希望在Windows中创建一个空文件使用以下命令：

Lets say we want to create an empty file in windows with the following command:

type nul > C:\does\not\exist\file.txt

目录不存在，所以我们得到了错误：

the directory does not exist, so we get the error:

The system cannot find the path specified

如果您打印出％ERRORLEVEL％的输出是：

If you print out the %errorlevel% the output is:

echo %errorlevel%
0

然而，命令没有成功！

Yet the command was not successful!

我注意到，Windows不设置％ERRORLEVEL％最后一个命令，如果你使用重定向。

I noticed, that windows does not set the %errorlevel% of the last command if you use redirection..

有没有办法解决？

推荐答案

您可以使用以下

C:\>type nul > C:\does\not\exist\file.txt && echo ok || echo fail
The system cannot find the path specified.
fail

C:\>echo %errorlevel%
1

我总是假设和放大器;＆安培;和||运营商使用的错误级别，但不apparantly

I always assumed the && and || operators used ERRORLEVEL, but apparantly not.

很好奇那个ErrorLevel被重定向错误后，只有当您使用设置||运营商。我决不会猜到。也我会永远都不屑于测试，如果不是你非常好的问题。

Very curious that ERRORLEVEL is set after redirection error only if you use the || operator. I never would have guessed. Nor would I ever have bothered to test if not for your excellent question.

如果你想要做的是设置在重定向失败ERRORLEVEL，那么当然你可以简单地做：

If all you want to do is set the ERRORLEVEL upon redirection failure, then of course you can simply do:

type nul > C:\does\not\exist\file.txt || rem

这篇关于文件重定向在Windows和％ERRORLEVEL％的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！