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Create directory if it does not exist

I am writing a PowerShell script to create several directories if they do not exist.

The filesystem looks similar to this

D:\
D:\TopDirec\SubDirec\Project1\Revision1\Reports\
D:\TopDirec\SubDirec\Project2\Revision1\
D:\TopDirec\SubDirec\Project3\Revision1\

Each project folder has multiple revisions.

Each revision folder needs a Reports folder.

Some of the "revisions" folders already contain a Reports folder; however, most do not.

I need to write a script that runs daily to create these folders for each directory.

I am able to write the script to create a folder, but creating several folders is problematic.

"creating several folders is problematic" - what sort of problem are you having? Are you not sure how to write the cod? Are you getting an error message? Do the folders just not appear after the script is run? Different problems require different solutions.

P
Peter Mortensen

Try the -Force parameter:

New-Item -ItemType Directory -Force -Path C:\Path\That\May\Or\May\Not\Exist

You can use Test-Path -PathType Container to check first.

See the New-Item MSDN help article for more details.


For the lazy, there is a shorthand: md -Force c:\foo\bar\baz
For those who don't want any output when the folder is created, add "| Out-Null" at the end
What will -Force actually do? The documentation says "Forces this cmdlet to create an item that writes over an existing read-only item". Will it delete an existing folder? It should be clear in this answer.
@PeterMortensen In the case of directories, forcing them does not clear out existing contents, it only suppresses the error message saying it's already created. This command will also create any intervening folders necessary, and the contents of those folders are also safe if they already exist.
Warning: This will proceed silently if there is a file at the path, unlike [System.IO.Directory]::CreateDirectory('path')
n
ndemou
$path = "C:\temp\NewFolder"
If(!(test-path -PathType container $path))
{
      New-Item -ItemType Directory -Path $path
}

Test-Path -PathType container checks to see if the path exists and is a directory. When it does not, it will create a new directory. If the path exists but is a file, New-Item will raise an error (you can overwrite the file by using the -force argument if you are risky).


Nice! This silences output if the directory already exists (because it uses test-path).
Why the option -Force?
@KCD to account for Schrödinger's Directory
r
rkyser
[System.IO.Directory]::CreateDirectory('full path to directory')

This internally checks for directory existence, and creates one, if there is no directory. Just one line and native .NET method working perfectly.


Can I do a local / relative path to my current working directory?
@AaronFranke you can do using [System.IO.Path]::Combine($PWD.Path, 'relativeDirectory')
S
Steve Taylor

Use:

$path = "C:\temp\"
    
If (!(test-path $path))
{
    md $path
}

The first line creates a variable named $path and assigns it the string value of "C:\temp"

The second line is an If statement which relies on the Test-Path cmdlet to check if the variable $path does not exist. The not exists is qualified using the ! symbol.

Third line: If the path stored in the string above is not found, the code between the curly brackets will be run.

md is the short version of typing out: New-Item -ItemType Directory -Path $path

Note: I have not tested using the -Force parameter with the below to see if there is undesirable behavior if the path already exists.

New-Item -ItemType Directory -Path $path

this also works for a hierarchy of directories md "C:\first\second\third create them all.
in the above, if the third doesnt exists, how can i create a "folder called "third"
P
Peter Mortensen

The following code snippet helps you to create a complete path.

Function GenerateFolder($path) {
    $global:foldPath = $null
    foreach($foldername in $path.split("\")) {
        $global:foldPath += ($foldername+"\")
        if (!(Test-Path $global:foldPath)){
            New-Item -ItemType Directory -Path $global:foldPath
            # Write-Host "$global:foldPath Folder Created Successfully"
        }
    }
}

The above function split the path you passed to the function and will check each folder whether it exists or not. If it does not exist it will create the respective folder until the target/final folder created.

To call the function, use below statement:

GenerateFolder "H:\Desktop\Nithesh\SrcFolder"

This one is not the easiest one, but is a easy one for understanding.
suppose, if iam having a path "\\shared1\folder1\" and i wanna create a LOGS folder in this path, if it doesnt exists, how can i code? because \\shared1\folder1\ , is a variable and not a hardcoded one. i mean, \\shared1\folder1\LOGS must be created if it doesnt exist.
P
Peter Mortensen

I had the exact same problem. You can use something like this:

$local = Get-Location;
$final_local = "C:\Processing";

if(!$local.Equals("C:\"))
{
    cd "C:\";
    if((Test-Path $final_local) -eq 0)
    {
        mkdir $final_local;
        cd $final_local;
        liga;
    }

    ## If path already exists
    ## DB Connect
    elseif ((Test-Path $final_local) -eq 1)
    {
        cd $final_local;
        echo $final_local;
        liga;  (function created by you TODO something)
    }
}

P
Peter Mortensen

When you specify the -Force flag, PowerShell will not complain if the folder already exists.

One-liner:

Get-ChildItem D:\TopDirec\SubDirec\Project* | `
  %{ Get-ChildItem $_.FullName -Filter Revision* } | `
  %{ New-Item -ItemType Directory -Force -Path (Join-Path $_.FullName "Reports") }

BTW, for scheduling the task please check out this link: Scheduling Background Jobs.


P
Peter Mortensen

There are three ways I know to create a directory using PowerShell:

Method 1: PS C:\> New-Item -ItemType Directory -path "C:\livingston"

https://i.stack.imgur.com/rtvCV.jpg

Method 2: PS C:\> [system.io.directory]::CreateDirectory("C:\livingston")

https://i.stack.imgur.com/a2TA2.jpg

Method 3: PS C:\> md "C:\livingston"

https://i.stack.imgur.com/tBN1V.jpg


Note that ` md ` is simply a Powershell default alias for ` mkdir ` (make directory), a windows command similar to Linux/Unix mkdir. ref: ` Get-Alias md `
P
Peter Mortensen

From your situation it sounds like you need to create a "Revision#" folder once a day with a "Reports" folder in there. If that's the case, you just need to know what the next revision number is. Write a function that gets the next revision number, Get-NextRevisionNumber. Or you could do something like this:

foreach($Project in (Get-ChildItem "D:\TopDirec" -Directory)){
    # Select all the Revision folders from the project folder.
    $Revisions = Get-ChildItem "$($Project.Fullname)\Revision*" -Directory

    # The next revision number is just going to be one more than the highest number.
    # You need to cast the string in the first pipeline to an int so Sort-Object works.
    # If you sort it descending the first number will be the biggest so you select that one.
    # Once you have the highest revision number you just add one to it.
    $NextRevision = ($Revisions.Name | Foreach-Object {[int]$_.Replace('Revision','')} | Sort-Object -Descending | Select-Object -First 1)+1

    # Now in this we kill two birds with one stone.
    # It will create the "Reports" folder but it also creates "Revision#" folder too.
    New-Item -Path "$($Project.Fullname)\Revision$NextRevision\Reports" -Type Directory

    # Move on to the next project folder.
    # This untested example loop requires PowerShell version 3.0.
}

PowerShell 3.0 installation.


S
Styx

Here's a simple one that worked for me. It checks whether the path exists, and if it doesn't, it will create not only the root path, but all sub-directories also:

$rptpath = "C:\temp\reports\exchange"

if (!(test-path -path $rptpath)) {new-item -path $rptpath -itemtype directory}

P
Peter Mortensen

I wanted to be able to easily let users create a default profile for PowerShell to override some settings, and ended up with the following one-liner (multiple statements yes, but can be pasted into PowerShell and executed at once, which was the main goal):

cls; [string]$filePath = $profile; [string]$fileContents = '<our standard settings>'; if(!(Test-Path $filePath)){md -Force ([System.IO.Path]::GetDirectoryName($filePath)) | Out-Null; $fileContents | sc $filePath; Write-Host 'File created!'; } else { Write-Warning 'File already exists!' };

For readability, here's how I would do it in a .ps1 file instead:

cls; # Clear console to better notice the results
[string]$filePath = $profile; # Declared as string, to allow the use of texts without plings and still not fail.
[string]$fileContents = '<our standard settings>'; # Statements can now be written on individual lines, instead of semicolon separated.
if(!(Test-Path $filePath)) {
  New-Item -Force ([System.IO.Path]::GetDirectoryName($filePath)) | Out-Null; # Ignore output of creating directory
  $fileContents | Set-Content $filePath; # Creates a new file with the input
  Write-Host 'File created!';
}
else {
  Write-Warning "File already exists! To remove the file, run the command: Remove-Item $filePath";
};

J
John Bentley
$mWarningColor = 'Red'

<#
.SYNOPSIS
    Creates a new directory. 
.DESCRIPTION
    Creates a new directory. If the directory already exists, the directory will
    not be overwritten. Instead a warning message that the directory already
    exists will be output.
.OUTPUT
    If the directory already exists, the directory will not be overwritten.
    Instead a warning message that the directory already exists will be output.
.EXAMPLE    
    Sal-New-Directory -DirectoryPath '.\output'
#>
function Sal-New-Directory {
    param(
        [parameter(mandatory=$true)]
        [String]
        $DirectoryPath
    )
    $ErrorActionPreference = "Stop"
    try {
        if (!(Test-Path -Path $DirectoryPath -PathType Container)) {

            # Sal-New-Directory is not designed to take multiple 
            # directories. However, we use foreach to supress the native output
            # and substitute with a custom message.
            New-Item -Path $DirectoryPath -ItemType Container | `
              foreach {'Created ' + $_.FullName}
        } else {
            Write-Host "$DirectoryPath already exists and" `
                        "so will not be (re)created." `
                        -ForegroundColor $mWarningColor
        }
    } finally {
        $ErrorActionPreference = "Continue"
    }
}

"Sal" is just an arbitrary prefix for my own library. You could remove it or replace it with your own.

Another example (place here because it otherwise ruins stackoverflow syntax highlighting):

Sal-New-Directory -DirectoryPath ($mCARootDir + "private\")