Question

From this posting, I managed to replace a string in a directory’s subfiles with Powershell on Windows XP.

foreach ($f in gci -r -include "*.bat") 
    { (gc $f.fullname) |
       foreach { $_ -replace "D:","C:\path" }  |
       sc $f.fullname 
    }

Unfortunately, a few exceptional cases required a “C:\\” rather than a “C:\”.

I attempted to use the following command to fix this problem (replacing “C:\path\\” with “C:\\path\\”), but it fails:

foreach ($f in gci -r -include "*.bat") 
    { (gc $f.fullname) |
       foreach { $_ -replace "C\path\\","C:\\path\\" }  |
       sc $f.fullname 
    }

The error is:

Invalid regular expression pattern: C:\path\\

I attempted several variants in an effort to circumvent the problem, but all produce the same error (replacing line #3 above):

foreach { $_ -replace "C:\path\\\\","C:\\path\\" } |
foreach { $_ -replace 'C:\path\\',"C:\\path\\" } |
foreach { $_ -replace "`C:\path\\","C:\\path\\" } |
foreach { $_ -replace 'C:\path\\\\',"C:\\path\\" } |

Any thoughts?

Answer 1

For repalcing replacing “C:\path\” with “C:\\path\\”

use

$_ -replace "c:\\path\\\\","c:\\path\\"

The Match pattern is regex and ‘\’ needs to be escaped with an ‘\’.
The replace string is just a string, no needs escape characters