PowerShell: How can I suppress the error if file alreadys exists for "mkdir" command?

Consider:

PS Y:\> mkdir C:/dog Directory: C:\ Mode LastWriteTime Length Name ---- ------------- ------ ---- d---- 11/7/2013 10:59 PM dog PS Y:\> mkdir C:/dog New-Item : Item with specified name C:\dog already exists. At line:38 char:24 + $scriptCmd = {& <<<< $wrappedCmd -Type Directory @PSBoundParameters } + CategoryInfo : ResourceExists: (C:\dog:String) [New-Item], IOException + FullyQualifiedErrorId : DirectoryExist,Microsoft.PowerShell.Commands.NewItemCommand 

5 Answers

Add the -Force parameter to the command.

Use:

mkdir C:\dog -ErrorAction SilentlyContinue 

It is a best practice to not supress error messages (unless you have a valid reason). Check if the directory exists instead of just trying to create one. If it does, maybe you need to remove its contents or pick another a name? Like so,

if (-not (test-path "c:\foobar") ) { write-host "c:\foobar doesn't exist, creating it" md 'c:\foobar'|out-null } else { write-host "c:\foobar exists, no need to create it" } 

I just wanted to add that while suppressing the error is usually not best practice as you say, the command -Force runs much faster than checking if it exists prior.

Where D:\ is a RAM disk:

Measure-Command {new-item "D:\NewFolder\NewSubFolder" -ItemType Directory -force} 

First run (creating folder object): 5 ms

Second run (after folder exists): 1 ms

Measure-Command {if (-not (test-path "D:\NewFolder\NewSubFolder") ) { write-host "Directory doesnt exist, creating it" md "D:\NewFolder\NewSubFolde"|out-null} else { write-host "Directory exists, no need to create it"}} 

First run (creating folder object): 54 ms

Second run (after folder exists): 15 ms

Thank you Peter for cleaning up my post! You are the man!

Powershell 7 ( || didn't work):

(test-path foo) ? $null : (mkdir foo)